Sure! Here is the sentence with the correct structure and formula:

**Sentence:** My stomachache disappeared after I took the tablets.

**Formula:** Subject + Verb (past tense) + after + Subject + Verb (past tense) + Object.

**Breakdown:**
- Subject: My stomachache
- Verb (past tense): disappeared
- after: after
- Subject: I
- Verb (past tense): took
- Object: the tablets

So, the complete sentence is: "My stomachache disappeared after I took the tablets."