Bearded dragon front left leg not moving, what is potentially wrong with it/is there anything I can do?

My flatmate has a bearded dragon that he's entrusted his gf and me to feed and take care of while he's away. Simple enough task. I know its quite young and was at the vet roughly 1-2weeks ago and was calcium deficient and has been having spasms but was being treated with a calcium spray. I've been away for 2days in which time it(no idea if male or female) has been fed as usual with mealworms. I got back today and feed it mealworms dipped in the most delicious white dusting thing and it chows down on 2 of the 4 i drop in(is that it not eating properly?). I noticed when it went for those unfortunate worms it was dragging its front left limb, no movement in it whatsoever which is quite alarming. I know its basking lamp has been on from 9am-10pm every day, its heat mat has been on the whole time and its been fed regularly. It seems to just chill out in a corner of the the tank and not move much. I can't see any swelling,bumps,bruises(can they bruise?) Or otherwise obvious afflictions, any insight would be greatly appreciated. Thanks