Wellbutrin SR and climbing the stairs

I just started taking the generic Wellbutrin SL 150mg last month. I was on generic Zoloft and felt like it had not been working for a few years (well, actually not working since I went on the generic form due to the high cost of the name brand.) My dr. told me to wean off Zoloft (cut pill in half) for a week while taking Wellbutrin. After the first week of this, I was scared. My heart was racing, I was out of breath just climbing the stairs (which I do a lot every day holding a baby...never a problem before), hot flashes, dizziness, a heart burn feeling in my chest, etc. I called my dr. back and she said to continue taking Zoloft for another week. I felt better once I began it again. I gave myself another week taking both drugs and then stopped Zoloft for the last time. Since then, I have had horrible mood swings with bursts of anger and constant crying fits. I rarely feel good and am waiting for the energy to come that I read in other people's postings. Instead of energy, I am experiencing severe tiredness. I have just been tested for Celiac disease, which could explain the tiredness, mood swings, etc., but not to the extent of what I am currently experiencing. Since being on Wellbutrin, I feel like I am in a nightmare. My husband and kids don't know what to expect from me day-to-day. I want to get off this drug, but know I need to be on something This one works well for my brother, so I thought I would give it a try. I'm ready to go back on Zoloft and forget trying to find something that works better for me. I can't handle the mood swings and crying. At least with Zoloft, I was more mellow - just no energy.