Methotrexate and mouth sores

I am 28 and have lupus, I was put on 10 mg of methotrexate last week weekly. Im expierencing some really weird side effects, atleast I think there side effects. My lower abdomen became very sensitive, I couldnt even touch the area where my uterus is, and now my breast have enlarged by a whole cup size and become very, VERY sore. Like the sore you get when you first get pregnant but I had a tubal ligation 6 years ago so pregnancy is out of the question. My heart beat is irregular and caffene seems to realy make it worse. I am soooo tired too, omg. I can't believe how tired I have become. And my hair is falling out, every time I shower it falls out in handfulls. Has anyone else experienced any of these symptoms? If so please share!

In a low lose (prescribed for asthma) I experienced mild nausea, mouth sores and eventually, vertigo. Since Methotrexate binds with folic acid, once my doctor prescribed a supplement of folic acid, the mouth sores and vertigo subsided. The Methotrexate therapy in a low dose for 6 months improved a bad asthma flare greatly for me.