My period ended on April 22nd I had unprotected sex on may 2nd I was suppose to get my period on may 9th and even though my period in irregular I usually get it some where in the teens . I try-ed calculating All this on my own but when ever I did it . I never got it right but since I started using a period calender it has been pretty good with my days... I no its too soon to test I am just wondering if there is a possibility I can become pregnant

Yes, there is a possibility you could be pregnant. It could be due to an irregular cycle. Wait another week, and if still no period, try a pregnancy test. If it is negative, see what happens when you would expect a period for June and test again if necessary.

If you are trying to become pregnant, and even if you aren't, it would be wise to be taking a multivitamin with folic acid (most will have it). This helps to prevent some possible birth defects in very early pregnancy.