Sill no Period....10 hours later..?

so, my period hasnt come yet it was due today and now its midnight and i havent seen it yet. i am usually very on time. my are VERY sore which usualy i get before my period just not this close to the day. i feel like i have my period kinda mucusy but no period..... i have a few twinges in my stomach but thats it... why would my period be late other than Pregnancy. what maybe could cause this? ill wait untill Tomorrow or Tuesday to test... Im kinda scared to test. i dont wana jynx it and i'll be dissapointed if its a neg. hmm... do you think i could be pregnant... we have been trying? .... my last period was on July 23rd... can you calculte if i have it right that today being the day im due (19th) ... i am a full 28 day cycle.. ive counted and counted to many times maybe im wrong? thanks :)