Hey! So what you're describing sounds pretty common in those first few days — your body is literally adjusting to a new medication, and that can feel really strange and disorienting. The heaviness, the butterflies, that floaty-but-not-quite-tired feeling... yeah, people talk about that a lot when starting SSRIs.
Here's the thing though: I can't tell you whether your dose needs adjusting or not, because that's really something to check in with your prescriber about. They'll know your full picture and can help you figure out if what you're experiencing is normal adjustment stuff (which often settles down in a week or two) or if something needs tweaking. It's totally fair to reach out and describe exactly what you're feeling — that's what they're there for, and it doesn't mean anything's wrong.
As for the placebo thing? Honestly, on day two, your body is already processing the actual medication, so it's probably not that. But also, the mind-body connection is real, so even if there's some psychological component mixed in there, the physical sensations you're having are still *real* sensations, you know?
The best move is probably to give it a few more days if you can (unless it feels unsafe or unbearable), keep notes on how you're feeling, and then touch base with your doctor. They might say "this is totally normal, give it another week" or they might adjust things — but you won't know until you ask.
How are you doing otherwise? Are you managing okay with the heaviness?