13dpiui spotting ?!

April ❄️

Woke up to some brown spotting this morning , I’m currently 13 dpiui and 15 dpt.. i tested yesterday and got a very faint line on a first response . Any ideas ladies ?! Have any of you guys had this happen? I’m a little early (if it’s my period ) ..I can post one of the other tests I took (not a first response) for reference lol