A third - party opinion...Am I pregnant ?

Oka, so I need a third party opinion. My last period was the first week of April. My boyfran and I had sex almost a week, if not sooner, after that. I haven't gotten my period the entire month of May. I do have irregular periods and only one ovary/fallopian tube. But I always have a period every month. I took a in - home pregnancy test. It came up negative. But I took it in the afternoon, I'm not sure if it really matters though. I'm having headaches and lower back pain. My hands and feet were swollen but I think those two symptoms don't come till later on in the trimester. I don't really have any breast tenderness/swollen. Is it actually possible that I could be pregnant ? I know I need to take another test, but I wanted to wait another week or two to see if it was just a coincidence. Any opinions ?