hi good day, My menstruation period is delayed. about 13 days, since im expecting it to come on 5th of March. I usually have 27 cycle, so my 27th cycle should be on 5th of March. But 27th and 28th February, I had sex. I tried the HCG test last March 13 and 16 but its negative. Before I was so stress, exercise so hard (morning and evening) then took many times on anti allergy (cetirizine). Do i need to take another pregtest?