If a medication has a long half life, can you still be feeling it later?
Yes. You will continue to feel its effects until the amount in your system drops below the level that is effective for you. That varies from person to person so it's impossible to say how long a med will continue to provide protection.
I've been feeling waaaay better this week (since I started taking it nightly).
Meds that have a half-life longer than 24 hours will build up in the system when taken daily. When taken daily Klonopin plasma levels will typically stabilize at 2-3 times the peak level of a single one-off dose.
I went from having panic attacks all day/every day, to now I don't even feel anxious for 5 minutes a day. But I don't know if it's actually the Klonopin making me feel better or if my Prozac finally kicked in. Or if I just feel better by chance. Or maybe I just felt awful the last few weeks by chance...?
It might be all of the above, though I suspect it is mostly the Klonopin.
I'm just wondering how the "half life" works.
I wanna know if I'm gonna start feeling like total crap when I go back off the Klonopin (it's now been 6 days).
Maybe. It depends on many factors. However, if you convince yourself that you'll be "feeling like total crap" then your probably will as the mind has a nasty habit of making our nightmares come true.
Wanna know what to expect cuz I'm really dreading calling them tomorrow to let them know how good I've been feeling (because they're probably gonna tell me to stop the Klonopin before I get addicted... And I'm probably gonna cry.....)
There's no need to. Think of Klonopin as just a small part of the journey, not its destination. Also make sure you tell them that you've only been taking half the prescribed dose to show you're not abusing it.