What Causes Cramping And Dizziness With Delayed Periods?

Hi, This questions if for an OB-GYN, I m worried I may be preganant and was wondering if the symptoms I m feeling are possible signs I am or not. My last menstrual cycle was in mid July (first day of last cycle was 7/10 or 7/11-7/14 r 7/15). My next cycle should be around this time. I have been experience headaches and mild cramping and dizziness on and off since yesterday but haven t seen the typical brown reddish blood associated with the beginning of my cycle. I checked cervical fluid and it was pretty watery and slippery until yesterday. I can provide more detail if necessary. Any help? Thank you