PLease Helptaking metformin?

Hey whats up u guys, well Ive been taking mEtformin for about a 1 mth 1/2 now was first on 500mg now on 1500 mg a day and taking a prenatal vitimin doc prescribed, I was put on this med to regulate my cycles so my brain can send a signal to my body to make and release an egg. The problem is at first i had a light bleeding for like 2 days.Well accouple of days ago at night I had some bad sharp pains in my lower abdomen and it has went away but ive since been feeling really sick not throwing up though, gas, diahrea cramps i dont wanna eat anything cause i get nasusea , i feel tired and weak the works. whats going on here , are these side effects are should i take a pregancey test, are should i tell my doc to take me off this stuff