Feeling down

I have been taking metformin for a month now and have lost 30 pounds and last week i was starting to think i was pregnant i had all the symptoms and i was so excited then i started spotting then the next day i had a heavy flow lots of clots then next day spotting again then next day done so not only am i upset that im not pregnant(i cried) but also upset that my period is still wak. Sorry for long post just wanted to vent