yes i ahd exactly same problem when first starting on mtx for me Rheumt specliaist said it was called weaning off phase and meant dose not high enough after 2 increases this did stop for me.
wish u well do let doc know who precibred mtx as onyl they can increase dose.
ive been on mtx sicne feb 2008 and now stable at 15 mg.
in mean time ask gp for medical input how to aleivate those drop dpwn days.
all best melly c