Its hard to say whether your symptoms are related to ovulation or pregnancy. I would not worry about pregnancy if you used condoms every time. If he did not actually ejaculate inside of you then there is no way you could be pregnant. Also, have in mind that there are other things that could cause such symptoms or menstrual changes. Things like medications or drugs, being under a lot of stress, anxiety issues and flu.
If you are still worried about pregnancy then I would definitely suggest taking home pregnancy test. They are pretty reliable and accurate. Just note that if you are going to take one, make sure you take it first thing in the morning when you wake up for the most accurate results. Also, make sure it has been at least 10 days since your last intercourse. Hope this helps