C02 Pressure

I switched over from a single to a double tap config on my kegerator recently and in order to do this, I purchased a C02 distributer (with check-valve). I set my lines up correctly, and the beer in my keg carbed up nicely. When I went to pour, it poured slow, which I am OK with. But, when I checked the C02 regulater I was down to 3 or 4 PSI (I normally set around 10). It didn't budge much. This was last night. This morning, I went to disconnect and bring in the tank to exchange, assuming that I was about out of C02. There seems to be plenty of C02 in the tank, so now I am not sure what to think. I hooked it back up and I was back at 10 PSI. Anybody have some thoughts? Is it possible my regulater is going bad?