If you had unprotected sex then you can get pregnant. If your cycle is usually 30 days long then you probably ovulate on CD 16. Since sperm can live for 3-5 days I'd say the odds are good that you could be pregnant. You are most fertile in the days before you ovulate.
I agree. You could have been ovulating or about to ovulate when you had sex. The chances of pg each month when you are trying and doing everything right is about 20-25%, so it's not a guarantee that you are pg, but it is a definite possibility.
Good luck with whatever you are hoping for!!
Thankyou both for your comments. Thats helped a lot. x