Hello. My Name Is Carmilla. I Have A Problem And

Hello. My name is Carmilla. I have a problem and I was wondering could you help me! Ok at the beginning of this month on the 2nd I had mild cramping. On the 3rd I had bleeding like my cycle was on for the month. However that night round 10pm it went off. The next day on the 4th I had just spotting a few time out that day til round 5pm. Before any of this happen last month in December I didn't get my cycle it skipped that month and also on dec. 30 and 31 I had unprotected sex with my fiancé. I am very puzzled at this could anybody help me!!!