Could there be something wrong with the release mechanism of my Wellbutrin? I take 450 mg of generic Wellbutrin XL every morning.. I always feel really good for about 2-3 hours after I take it, then suddenly my mood plummets and I feel like my head is in a fog and I can't think clearly.. and I feel like that for the rest of the day. I'm taking the same generic I've been taking all along (Par)... could they have changed something about their pills? I can't figure out why I feel like this all of a sudden. I've never had issues with Wellbutrin before. Anyone ever go through this?