test lines getting lighter

Okay so four days ago I got my first positive test on a cheap strip, a clear blue, and a clear blue digital.  Yay! But I have been obsessively testing since and they are getting lighter.  I don't know whether it is because I'm really thirsty and I'm just using cheapies now or if I'm having a chemical.  I'm a mess of tears and I'm really upset.  Any input would be appreciated.