i hd sex fr frst tym in jan widout protection hd an i pill aftr 5hrs...thn had a nrmal period..agn unprotctd sex in mid february..hd an ipill after 2 days..thn aftr 1 week hd bleeding/ spoting for 2 days.. after tht i hd normal periods for 3 days(but fr me normal is 5days)..in march agn hd spotting for 2 times wd d gap of 1 week.....nw in april im hvin brown sometimes grey coloured discharge with blood..which is thick n is atlst 1teaspoon...no foul odour..n is accompanied with mild pain n sometimes pulsations over vagina..!!! my this month periods are due in another 10 days....in between i did 3 pregnancy test and all were negative...... so please suggest me what can be the reason for this......!!!!