You might want to be worried. Beardies mask their pain and injury till it is too late most of the time. If his toe is gushing blood that really isn't good. Has it started pussing at all? Like a yellowish color?
Open wounds on bearded dragons can take up to a month to heal. Could you post a picture?
I would really suggest that you go to a vet, you don't want to get infected. If it does, then you will have some real problems trust me. You want to take care of the problem before you actually have one.