Trizepatide symptoms change week to week?

Started 0.8 mg tirzepatide 9 days ago as a microdose.
Week 1:
Day 1: No noticeable effects.
Days 2–3: Appetite suppression kicked in, along with pretty intense fatigue (honestly almost unbearable). No nausea or GI issues.
Days 4–6: Fatigue resolved, but the appetite suppression continued.
Days 7–8: Appetite gradually returned to normal.
Overall, I thought it was a really reasonable response to the medication.

I took my second 0.8 mg dose on Thursday and expected a similar timeline. It’s now almost 48 hours later, and I feel…nothing.
No fatigue, no nausea, and no noticeable appetite suppression (although I haven’t really tested it with a large meal yet).
Is this kind of week-to-week variability common? I know I’m taking a microdose rather than a full therapeutic dose, but I responded really well the first week and definitely felt the medication. Is it possible for the same dose to have almost no noticeable effect the following week, or have others experienced this and then had the effects return with later doses?