I am about 4 days late for my period. I know that's not a lot but I don't use birth control (we only use condoms) and I am getting paranoid. I have taken two pregnancy tests, 2 days apart and they were both negative but I'm still worried.

My question is, how many days should I wait before taking another test?? Obviously if I start my period in the next few days I won't take one but I don't want to waste a test if it's not going to be effective.

Any input??