pregnant or just the flu?

I was on birth control for a few months and my doctor decided to put me on a different pill that she said had less hormones but was still just as effective as the last one i was on. well my partner lives out of state so i decided not to take them as soon as they were given to me (i know stupid idea) i barely remembered about them 3 days before he was supposed to come down here so by the time he was here i was only on the pill for 3 days. we ended up having sex that same day many of times without a condom and (sorry for being descriptive) but he ended up cumming inside of me various times. i had my period from december 26-december 30th. we had sex january 1st-3rd and for some odd reason i got another period around january 5th that only lasted a couple of days. recently i’ve been so exhausted for no reason, i haven’t been hungry, I’ve been getting really bad headaches, there are times where i feel dizzy, i was throwing up all day monday, all day wednesday and I’ve been sleeping SO much. I’m just not sure if there’s a possibility if I’m pregnant or if it’s just the flu? I havent had a cough or anything like that so Im a little scared. I took an at home pregnancy test about a week ago and it came out negative I’m just not sure if it was too early. Thanks in advance