No I really dont think you are pregnant. Here is why, #1 if you ovulated only a couple days before you got your period, there would not be time for the egg to implant before the uterine lining was shed. #2 you got you period
did you have normal bleeding. I know you said that it was shorter. You do need to know that sometimes women do have spotting during ovulation and mistake it for a period. You should not have unprotected sex at anytime if you are concerned about getting pregnant.
Also , pregnancy symptoms generally don't occur that early.
Good luck and if you still ahve concern please go to a clinic or doctor and get checked out, it is the only way to find out for sure!!!