New diagnosis. My biggest issue is fatigue and brain fog, though I do have some joint pain in hands mostly but it is minimal. Doctor prescribed Methodrexate but im very concerned about it causing more fatigue. Help?

I struggle so much with fatigue and brain fog that it has already affected my ability to do my work etc. I don't know if I can justify taking methodrexate if it causes more problems for me this way. I tried to talk to my doctor but she didn't seem super receptive to my concerns.
She diagnosed me with RA and unspecified MCT disease. My main symptoms are extreme fatigue, brain fog, peripheral neuropathy, occipital neuralgia. I do have joint pain in hands somewhat and a bakers cyst that has gone down quite a bit and some hip discomfort occasionally. But I can deal with those. I cant deal with the fatigue. I am very very anxious about taking methodrexate for this reason. She did prescribe a methylfolated folic acid as well but as far as I understand this is to help with nausea mostly? Idk what to do. I also feel like, while I definately have some markers: positive RF igm and T igm as well as dopler signals on ultra sound, I don't have a lot of tge other high indicators. Just looking for guidance and help. Thanks much.