Looks like a coastal to me ...and a nice one too Only 3 feet long and three years old!!! That does not sound right....because from the pictures it does not appear to be underfed......mine were June/August 05 hatchlings and are pushing 4 feet! Eatting nothing bigger than a large rat fuzzy a week until about 4 weeks ago...now they are eating small rat pups.

Coastals are great snakes and my pair have been a pleasure to keep so far. Sounds like you have everything under control. Feed them and house them properly and they will grow

....and female coastals have the potential to reach 10+ feet long (maxing out at 12'-13'), so be prepared to house a wopper if you get ahold of those genetics