How much CO2 you're getting into your beer all depends on the temperature your beer is sitting at and how many lbs of pressure you're putting into the keg. Check out this forced carbonation chart
to figure out what PSI you need to set your regulator.
I usually keep my kegged beer at room temp while it's carbonating so I set the PSI on the regulator at 27 and let it sit for two weeks before I put it in the kegerator and chill it down to 41 degrees for serving. My serving PSI is usually 11-12 PSI. Works like a champ.
The really foamy head on your beer is probably because you either have the wrong size dispensing hose or because your dispensing hose is too short. If you're using standard dispensing hose that's 3/16" then you'll want to have 1/2 foot of hose for every PSI on your regulator. This keeps proper restriction on the beer not allowing the CO2 to escape into the line before the pour. I have 6 feet of dispensing hose since I keep my regulator at 12 PSI. You'll want about 7.5 feet of hose if you're dispensing at 15 PSI. You can increase/decrease the length of the hose to adjust to your setup.
Hope that helps!
Crush, Mash, Sparge, Boil, Cool, Aerate, Pitch, Ferment, Condition, Keg, Carbonate, Chill, Drink, Repeat!Read it
. C'mon, you know you want to!