Evaporation Line?

Okay ladies, four days late here.... I took a test, first of all. I’ll admit. It said to hold test in cup for 20 seconds and that didn’t register until after the fact and I only did like 6. Waited like 2-3 minutes and it was negative, looked again about two hours later before I threw it away and the positive cross was there and faint. Used clearblue digital test. Any thoughts ? Obviously re testing in a couple days. Tia