I think it's fine but medium rats once a week seem a bit much to me. I feed mine every 10-14 days when they get to small/medium rats or bigger prey. Thats just my opinion though.

I would think you should wait every two weeks.. i guess? I'm not really sure, mine went off feed for only two-three weeks so I haven't really had this problem.

How long has it been? If it hasn't been to long I wouldn't worry, especially if he doesnt seem to have lost any weight.