Very confused 😕

I had two HSG tests done. One on February 25th and then the second one on March 28th. I started my period in March on the day I regularly start and had light cramping no bleeding. My doctor then ordered Me to have a second HSG done. After that one I had horrible cramping and bled lightly for 2 days. I have not started my period this month and am a week late. I just came back from a follow up visit and took a pregnant test while there and it came back negative. My question is has this ever happened to anyone? I really thought that this month was the month we'd be pregnant. I have look at my calendar and BD on all days I was very fertile. Yesterday I experienced light pink bleeding that only lasted an hour and it hasn't returned. I am very consumed. Any suggestions would help!