spotting

Okay this sounds stupid but my boyfriend and I had sex about 12 times unprotected within 3-4 weeks.  One of those times were when I was ovulating which said 15% chance and another at 33% chance. But he always pulls out on time I'm sure of. Not sure about Precum because one of those 12 days we did it 4 times in one day. But, lately I've been fatigue, cramping, etc. and yesterday I started spotting light pink. My period isn't due until a week. I took a test yesterday but it came out negative. Was that too early to test? Should I wait until next week to test again? Or could this be my period coming on early ?