Please i need advice

On the 7th... my fiance accidently came inside of me. Usually we pull out. My ovulation window was 2 days later. My period is not due until the 28th. Today is the 21st. For over a week.... ive had dull cramping. (I never get cramps at all with my period). And ive been having crazy mood swings too. I took a pregnancy test yesterday, negative. But it still might be early. What are my chances? Im freaking out because of the cramping ive had.