...Dr. says that most of the drugs are interchangeable as they are the same things just delivered differently.
Get a new doctor. Seriously, no doctor worth their salt would ever over-simplify to that extent. It is a completely false assertion as well. They all have different receptor actions and affinities not to mention some are reuptake inhibitors, some are catecholamine releasers... Your doctor isn't doing you any favors if they don't even have a basic understanding of the properties these meds have.
If you were switched to Wellbutrin from Effexor, you may very well be going into Effexor withdrawal if it wasn't done properly. I'm not sure about Ritalin to Adderall, I always avoided those drugs even if they said I needed them.
Eltroxin may need to be adjusted - Wellbutrin, Adderall, Effexor, and Ritalin are all stimulants in their own ways and an improperly functioning thyroid may not be able to keep up with the changing metabolism so have that checked when you are acclimated to the new regime.
Coversyl has a wide range of drugs that it interacts with - I was going to ask you if you have considered giving an atypical a try, specifically Geodon, but that drug is specifically not compatible with Coversyl along with many other atypical antipsychotics, the TCA antidepressants (which unfortunately are the only ones that have ever beaten placebo to any significant degree), and a bunch of other medications as well.
I don't really have any suggestions for you. It takes roughly 2-3 weeks usually for Wellbutrin to kick in but if you weren't ramped off of Effexor properly, there will be a dose-dependent discontinuation syndrome that will mount itself.
By the way, tolerance has no bearing on Wellbutrin's ability to lower your seizure threshold. Just because it isn't having any clinical effects that you can notice doesn't mean that it hasn't lowered your seizure threshold and being on Adderall only exacerbates the seizure risk. Wellbutrin is also not a drug that exclusively triggers seizures in people that have a history of them, it is well-known that even therapeutic dosages can bring on seizures in those that have never had them before.