Tongue and lip tied?

She's always had difficulty latching but I thought it was just because I have flat nipples. She is now refusing the nipple shield, her pacifier and my breast. She just sits there and fumbles with anything that goes in her mouth like she doesn't know what to do. When I do finally get her to latch, it is very shallow and she nurses for like an hour or more but it often includes her unlatching many times and crying hysterically. I was up for 3 hours last night going through this. The doctor won't see us till mid-July and I am at wits end. Can anyone tell me if this is a tongue-tie and any suggestions for what I can do in the meantime?