Possibly pregnant

So I took a test earlier and definitely saw a line faint but it was there within the 3 minutes the directions say to wait. I held onto the test for a little while and checked it again and the second line has faded can still see it a little but does anyone have any experience with this? My breasts are sore but not experiencing any other typical period symptoms (I’m about 2 days away from my expected period) UPDATE: retested today with a first response stick instead and also got a faint line. I’m due for my period tomorrow can that cause a false positive? I plan on testing again tomorrow with a digital stick