Evap lines on 3 tests in a row?

I'm TTC baby #3 and have had a lot of pregnancy symptoms. I took a test last night and it was originally negative and then an hour later I glanced and it had a second line. I tested with FMU today, and same thing happened. Tested again this afternoon with a different brand of test, and for the third time, I saw an evap line about an hour after testing. I know the tests are not valid after 10 mins and I'm not considering them positive. But for this to happen 3 tests in a row make me wonder if this is the start. Anyone else?