spotting before period

Sarah
I'm having some darker brown spotting and my period isn't due until mid-February. Is it too early to test for pregnancy even with an early pregnancy test? My cycle length is difficult to predict because I was on a birth control pill up until late December and have only had one period since then that started on 1/14. My period rarely came around while I was on BC, so I'm only now learning about my cycle. My husband and I had sex 4 times during my fertile window according to Glow, which just passed at the end of last week.