L.J.
You should wait. Periods can be late. Even if you did make an appointment, you would probably have to wait a few weeks to see the doctor anyway. Wait a few days and try to relax. If you period still hasn't come three days from now, take another home test. By that time, you will probably get a bright second line on the test if you are pregnant. BTW, any second line at all, even a very faint, yet colored one, is a positive test. False negatives are common. False positives are very rare.