Pregnant?

I had cramping for about an hour on 7/8 on 7/13 I had spotting that lasted two days only was there when I would wipe. No other menstrual symptoms came along with it and I normally have horrible cramping and low back pain. I took a test 7/20 and it was a BFN. We have been trying for 2 years now and don't know on whether I should still take another test later or not.