I have tickets to an all ages show, but one ticket says over 21 will i be able to be with my under 21 friend or do i need a new ticket?

you won't need a new ticket. they just seperate it like that so under 21 people cant go near the bar. shouldnt affect you unless you try to bring alcohol out of the designated area.

Should be okay

Yes it is an all ages show one ticket says under 21 and one says over 21

Are you positive it's an all ages show? You may need to verify with the venue.