Try to conceive!

My husband and I have been trying to concieve for the last month and I'm getting discouraged. My last period started October 7 and I got my paragard iud out September 29. Well last night we were having sex, we bumped heads and I immediately started balling my eyes out for no reason. I've been this way for a week now and having weird stomach pains, but just took a pregnancy test on 10/16/14 and it was a BFN! Help!!