Proper medication after miscarriage

Hi everybody. I have my second miscarriage 2 days ago but when I visited my doctor he seemed to be careless and he didn't ask me for any tests and didn't give me any medication. He just told me to wait 3 months before trying again. But miscarriage is a horrible experience I am afraid to go through the same cycle again before doing any action or taking any medication I hate the feeling that I can't do anything to protect my baby. From your experiences what are the safe medication you tried or your doctor told you to take that I can take without doctor prescription that may help to prevent mescarriage again like folic acid or baby aspirin.