Overcarbed Undercarbed or just too warm?

[majake]

Hey I know I should be more patient, but I found out I'm hosting a party tonight and really wanted to have beer ready. I racked it into the keg today at room temp and hooked it up to 40psi and rolled it around on the ground for 10 or 15 minutes letting co2 in. Then I popped it in my kegerator at 30psi and went to work. It's now 3 and half hours later and the beer is still not very cold. I dropped the pressure to 13psi, purged the keg, and hooked it up to pour a glass. The glass came out all head with a little flat beer in the bottom. I know this is usually a sign of overcarbonation but could it simply be because the beer is warm? I'm not sure whether to be carbonating the beer more or letting it decarbonate. There is no check valve in my keg and pressure has been reading a constant 13psi for 20 minutes so I don't think its overcarbed but this is my first time force carbonating so I'm not sure. What should I do? And I know I should have been patient to start with but its too late for that now so what should I do at this point? Thanks!