Late period

Hey there! My last period was on March 9 and it lasted the usual 7 days. My next predicted period was suppose to come on April 22 (according to Flo) but it's been 2 months and I've yet to have a visit from Ms Flow. In between April , I did had slight bleeding (a streak of red mucus like?) And it was only for a day or two. Took a pregnancy test the other week but came out negative. Should I do another test to rule out pregnancy and then wait for period to come? Or should I head to the clinic to get checked? I've had irregular periods before giving birth to my son but it has been regular since. Looking forward to hear some advices please. Thank you!!