Since you've had this snake less than a week, you have no reason to be concerned. Give it a week to settle in, and then you can start thinking of feeding. It may take a couple weeks for it to really start feeling comfortable.

And if you are concerned, call LLL Reptile and talk to them. They are VERY helpful. I've been to their Oceanside and Menifee stores, and have been very pleased with their customer service (though I haven't bought reptiles from them, they've been very helpful with any questions I had or helping me find the feed or supplies I need).