Weird period but negative test

Okay ladies so I had been missing my birth control and my husband and I haven't been really trying hard to get pregnant but it wouldn't be a bad thing if we did. So I normally have 5 day periods and this past period was only 2DAYS!!! Weirdest part was that it was brown and very light. I took a pregnancy test a couple days after I got off my period but it was negative and I thought maybe it wouldn't show by then... But I haven't taken any birth control this month because I'm nervous I might be but also don't wanna go out and get another pregnancy test and be disappointed that I'm really not pregnant. Please comment your thoughts!