sometimes this just happens,, it happens when u least expect!,, at least you know you can have children. If after a year you havent concieved then doctors will intervine...are you stressed? It could also be the quality of the sperm. it changes.. i know with us, hubby had 3 tests, 1st one slow swimmers, 2nd one poor quality, 3rd one, they were fine. and i have 2 kids now!
Just relax and dont stress it will make it worse...(i know thats easy to say)