Evaporation line or not?

This is the first month my husband and I have ttc. I BD throughout the month and especially on the days I thought I was ovulating. It's hard to say if I have any symptoms. I drink plenty of liquids already so I'm always in the bathroom. I have no tenderness though I should since I should be starting my period tomorrow or in the next couple days and I normally get really sore . For a year now I've gotten slight heartburn/acid reflux, but a couple nights ago I layed down and started feeling sick. Sorry if gross but I threw up in my mouth a little :( and had a nice big headache. No implantation bleeding that I've noticed as well. So this morning I took an hpt out of curiosity (It was the New choice brand from the dollar store), and I maybe sat and waited a minute to see the results. I of course figured it would be negative, so I just layed back in bed, but maybe 20 minutes later I looked at it again and it had a faint line that wasn't there before. It's pretty light but definitly there, and I know it could be an evap line, but I'm not sure. I may have walked away too soon, or it could have showed up after the 10 minute mark. It's pink in color just like the other line, and I thought evap lines were grey in color. Has anyone had this before? I'm going to test again in a couple days and see for sure if AF comes, but I just was wondering if anyone had similar experiences and was or wasn't pregnant.