Did Chute not check your activity when he gave you permission to apply straight to admin? Honestly, I don't think your activity would be considered bad if you were applying for moderator, but since you're applying straight to admin which requires more work to be put in, I think you should wait at least a week or 2. I understand that you may not be very active due to college, but that shouldn't be an "excuse" used just to have you 'let off' for bad activity.
I remember you as admin and I believe you did a decent job, but your activity needs to improve if you're going to reapply again.