negative test, but still pregnant?

Hi ladies,

I have a quick question. I've been keeping a close eye on everything last month. For example, on May 11th I had a lot of stretchy mucus, which I think completely stopped around May 16th.
Since about May 16th I've been having sensitive, sore breasts, but they don't look any different. (In previous months, this was only sensitive for about 2 days and then it went away).
I think I should get my period around this time.
I've also had cramps and lower back pain + frequent urination for a week now.
I took a test this morning but it was negative. Later in the afternoon I had a lot of stomach cramps again but no period, and now the cramps are less again.
Could it be that ovulation was much later than the stretchy mucus? Should I wait a few more days for a new test if I don't get my period?

Thanks in advance for your answers!