I have been biting my tongue in the center/middle when i eat. it will bleed for hours off and on but eventually heals. should i be concerned?

Tongue bleeding: You should see an ENT doctor for exam and possible biopsy. People usually bite their tongues on the sides rather than middle.

Tongue biting: I would have this area checked out. Oral cancer can cause swelling enough to bite and be reinjured and bleed. Could be related to a change in your dental work or dry mouth causing it to stick to teeth more and be pulled onto the chewing surfaces. Best to have it checked out by a dentist or oral surgeon.