Welcome, sanchezalexis!

1) Yes.

2) Yes, possible, but no guarantees and a lot of variables. It wouldn't be wise to count on it working.

3) No idea. People could probably turn up examples of about anything. Again, a ton of variables, and nothing can be definitively stated. Contounded by the fact that most people won't have that reaction whether long or short term.

4) I'd say yes, more likely. I'm more familiar with someone having the after-effect of depression from MDMA use. Still, I'm inclined to think you are right in suspecting the MDMA as the main culprit in your episode.

5) Yes, I think your reasoning makes sense. Which is not to say any kind of guarantee, simply that it's a reasonable thought process. Two thoughts. Keep consumption in check (Avoid going back to the 3g/day because even aside from any mania concerns, your experience shows it having negative impact on your functioning, even if you didn't consider it too concerning.) And two, indicas would be better than sativas.