Ovidrel

took an Ovidrell shot on Sunday July 20. I went to the doctor last Tuesday (July 29) for blood work. My nurse called me and told me that my progestrone level was at 12.5, which means that I ovulated. Right then I went and took and took an HPT, it came back postive. Later on I found out that the shot could be the reason for the test to have read postive. I took another one (which would be nine days after the shot) it also came back postive, but I took one on day 10 and it came back negative, I also took one today and it came back neg again:(! My breast have been very sore and I have experience some cramping.) (i also so have irregular periods) Any advice