Do you take your mtx orally or by injection? I've had problems w/ nausea/vomiting when I was taking Imuran, but now I take methotrexate via injection and I haven't had any nausea. I also take folic acid.
I was on methotrexate for about 4 weeks before I started to notice a difference. So far, things are going well. It is working better for me than any other med I've tried (Humira, Imuran, 6mp). I'm by no means symptom free but the frequency of the pain and d have decreased A LOT.
Best of luck to you :)