Setelah duduk terlalu lama, pinggang saya pegal dan saya harus membungkuk pelan-pelan.

Setelah means after. It introduces a time clause:

• Setelah duduk terlalu lama = After sitting too long

It works much like English after. In Indonesian, this time clause can come before or after the main clause.

• Setelah duduk terlalu lama, pinggang saya pegal...
• Pinggang saya pegal setelah duduk terlalu lama.

Both are natural.

Both are possible.

• Setelah duduk terlalu lama = After sitting too long
• Setelah saya duduk terlalu lama = After I sat / after I had been sitting too long

Indonesian often leaves out the subject when it is already clear from context. Since the rest of the sentence clearly refers to saya, omitting it sounds natural and efficient.

Terlalu means too, and lama means long or for a long time.

So:

• terlalu lama = too long

Examples:

• Saya menunggu terlalu lama. = I waited too long.
• Dia tidur terlalu lama. = He/She slept too long.

Pinggang usually refers to the waist, hips, or especially the lower back/lumbar area in everyday usage.
Punggung means the back more generally, especially the upper or whole back.

So if the pain is from sitting too long and feels like lower-back stiffness, pinggang saya pegal makes sense.

Roughly:

• pinggang = waist / lower back
• punggung = back

Not exactly.

Pegal usually describes a feeling of stiffness, soreness, or aching, often in muscles after sitting too long, exercising, or doing physical work.

Compare:

• pegal = sore, stiff, achy
• sakit = painful, hurt, sick (broader and more general)

So:

• Pinggang saya pegal = My lower back feels sore/stiff.
• Pinggang saya sakit = My lower back hurts.

Both are possible, but pegal gives a more specific bodily sensation.

Indonesian often does not use a verb like is/am/are in simple descriptive sentences.

So:

• pinggang saya pegal literally looks like my waist/lower back sore
• natural English translation: my lower back is sore

This is completely normal in Indonesian:

• Saya capek. = I am tired.
• Dia senang. = He/She is happy.
• Rumah itu besar. = That house is big.

It is repeated for clarity and natural flow.

• pinggang saya pegal = my lower back is sore
• dan saya harus... = and I have to...

You could sometimes omit repeated elements in Indonesian, but here repeating saya sounds clear and natural because the second clause has a different subject phrase structure.

Harus means must, have to, or need to.

In this sentence:

• saya harus membungkuk pelan-pelan = I have to bend over slowly

It often expresses necessity, obligation, or something the situation forces you to do.

Examples:

• Saya harus pergi. = I have to go.
• Kamu harus istirahat. = You must rest.

Membungkuk means to bend over, stoop, or bend forward.

It comes from bungkuk, which is related to a bent or hunched posture. With the meN- prefix, it becomes a verb:

• bungkuk = hunched/bent
• membungkuk = to bend forward / stoop

In this sentence, it suggests the speaker has to bend carefully because their lower back is sore.

Both are possible, but reduplication often makes the adverb sound more natural, gentle, or continuous.

• pelan = slow(ly), quiet(ly), gentle
• pelan-pelan = slowly, little by little, gently

Here pelan-pelan gives the sense of moving carefully and gradually.

You may also hear:

• perlahan-lahan = slowly, gradually

So:

• membungkuk pelan-pelan
• membungkuk perlahan-lahan

Both are natural.

Because it functions as an adverb describing how the action is done.

Indonesian often places adverbs after the verb:

• berjalan cepat = walk quickly
• bicara pelan-pelan = speak slowly/softly
• membungkuk pelan-pelan = bend over slowly

This is very common word order.

Indonesian verbs do not change form for tense the way English verbs do. Tense is usually understood from context, time words, or the situation.

This sentence could be understood as:

• a present result after a past action: After sitting too long, my lower back is sore...
• a narrative description in the past, if the surrounding context is in the past

The time relationship is shown mainly by setelah (after), not by verb conjugation.

It is helpful because Setelah duduk terlalu lama is an introductory clause.

So this punctuation is natural:

• Setelah duduk terlalu lama, pinggang saya pegal...

In informal writing, people may sometimes omit commas, but using the comma here is clearer and more standard.

Yes, depending on context.

By itself, harus does not mark past or present. So:

• saya harus membungkuk pelan-pelan can mean I have to bend over slowly
• in a past narrative context, it can be understood as I had to bend over slowly

Indonesian often relies on context rather than verb tense endings.

It sounds like normal, everyday Indonesian. The vocabulary is natural and common:

• setelah
• terlalu lama
• pinggang
• pegal
• harus
• membungkuk
• pelan-pelan

A speaker might also say similar everyday variations such as:

• Habis duduk kelamaan, pinggang saya pegal...
• Setelah duduk lama, pinggang saya sakit...

But the original sentence is perfectly natural and clear.