Suggest Remedy For Missed Period?

my cycles have been abnormal before. talked to my dr in oct 09 about getting pregnant. he then gave me provera to bring my cyle down and started me on clomid. stopped the clomid dec 09 or jan 10, and my cycles had begun to come regularly every 30 days. last cycle came on 4/4 and went off 4/7 or 4/8. no cycle for the month of may as of yet. is it possible that body has gone back to its old way or should i be concerned that i'm pregnant?