Thanks for the query to H.C.M. Forum.Metformin
don't interfere with menstruation
cycle, so don't worry about that.
As on previous occasion home test for pregnancy
brown discharge is there , cause may be due to pelvic inflammation. Vomiting
may be due to intake of metformin , because in few patients this develops nausea
If second pregnancy test is negative consult a gyane , if your age , which , you not mentioned in query, is around 40 years , think about premenopause .
Hope I have answered your question.
If further any question I will help.