Have Irregular Periods. Had Unprotected Sex. Started Spotting, Feels Tired, Cramps, Headache And Constipation. Am I Pregnant?

My periods are sometimes irregular. I had my period March 25-30 and had unprotected sex on the 1st of April. Now a week after my period i had very mild cramps , and the next day I had a light pink spotting when I went to wipe which only lasted for a few hours. I was wondering if it was possible for me to be pregnant? I ve been feeling tired, mild cramps & headaches , and sensations in my stomach an constipation . I don t want it to be all in my mind . I m not supposed to have my next period til May 7th. So I don t know if it s possible for me To be pregnant and how long would I have to wait to test. Thanks in advance.