Advice please...

Im feeling pretty emotional at the moment. Bit of background info... First mc was May 2013. Second February 2014. Didnt get my period for 11 months after that. Finally started getting my period again Jan this year and has been quite regular on an average 28-30 day cycle. Started Clomid 3 cycles ago. My period is currently 4 days late based on a 30 day cycle. Weird thing is i normally feel my period coming on with cramps, lower back ache, acne and really sore nipples about 3-4 days prior. This time i have absolutely nothing... The only thing i have is some reflux/heart burn and extremly hot flushes with headaches. Last time i poas was cycle day 28 with one blazing control line aka the dreaded BFN... Im too scared of testing again and being disappointed. Has this happened to any of you ladies?? Any advice? Do you think my period is just being a cow and will show eventually or there could be a chance of being pregnant with no symptoms?? We have bd like crazy, so any chance we could of fallen pregnant we have done it... Its such a punish!!!