Please read I’m not sure what’s going on!

I got my period on Monday I believe, and then by Tuesday night it was completely gone Wednesday I had some bleeding again but at night it was completely gone just a pink light color then this morning it was a pink/brown color super light again. Not sure what’s going on I am on birth control though. So I’m not sure if it’s my pill or if I’m actually pregnant but my period when I have it usually never stops at night and I usually have to wear a pad to bed need advice thanks!