I had unprotected sex with this guy 3 times the day after my period a month and a half ago and took 3 pregnancy tests but they showed up negative I don't know if I took them to soon or what but I have not had my period since then what should I do?

Since it has been a month and a half, now would be a good time to take the test, so if you mean you just took them, they should be valid. I will assume you followed instructions and used the first urine of the morning.

I took them a little before a month that I had sex.

If the tests are negative, its usually right. If your that concerned go to your doctor. Good luck!