Curious

So last week I was spotting light pink for 6days and then stopped I was expected to get my period on the 15th but didn't still have not but I have been having like nausea for two days then stopped and now my stomach feels like there's something there it feels like after a work out when your stomach is sore like that could this be because I'm pregnant or something else  ps. I took a pregnacy test last week n it was negative