What Causes A Delayed Period With Negative Pregnancy Test?

Is it possible foe me to be pregnant even after a neg pregnancy test? I only had one period in the past six months, if it even was a period. My period has never ever done this and before this i have always had regular cycles. Im feeling flutters, pelvic cramps, VERY frequent urination, also feeling sick from a smell or taste, and what seems to be bubbles popping or moving in my stomach. I know my body and this is most definatly not normal. I have a doctors appointment next week but it would be great to know something a little sooner because each day the fluttering gets more noticable.