I have a couple things for you. 1) if your doctors aren't explaining why they are or are not concerned about your child well enough to you so you understand why they feel that way, make them...if they still don't...get a new doctor. There is nothing worse than not understanding why something that seems not normal to you is just fine with them but you have no idea why!
2) my son had 2 sets of tubes and a little blood in both ears when they fell out. What I was told, for my son, is that the tube was pushed out earlier than it would have come out, by fluid and pressure in his ears (hence why he had a 2nd surgery, infections kept coming) and that since it was "pushed out" that it was irritated. Now when the second set fell out, he had gotten a double ear infection, which they treated and has been fine ever since (over 6 months), so the doctor said it was no big deal. With the first set of tubes, he kept getting the infections after the tubes were pushed out, so they put new tubes in. So, I never noticed blood, until one day a dried blood scabby looking thing was coming out of his ear. That was almost a month after the tubes had come out of the holes. So dried blood doesn't have to a concern.
3) when my sons tubes fell out the second time, he kept complaining about his ear bothering him or hurting, I took him to the Ped and the ENT and both said the tube was in his ear, stuck in wax and probably was bothering him, and once the tube in the right ear fell out (I saw that one come out) he stopped complaining. For the left year he just stopped complaining and the next time he was getting a check up they said the tube had fallen out, so I assumed they coincided. So, some of the pain maybe the tube is in there, but not in.
I don't know if anything in here made you feel better or helped, but I know it was scary for me. Best of luck!!