Some Type 2s take insulin too. It is confusing when you suddenly get something you've not had to think about before.
The basic difference is that Type 1 is an auto-immune disease. For some reason, the immune system starts attacking the insulin-producing cells in the pancreas. When enough have them have been destroyed, the body is no longer able to control its blood sugar, and needs insulin injections to replace the insulin the destroyed cells made.
There are tests that can look for the antibodies that are part of the auto-immune attack.
Sorry you're having to deal with epilepsy too. I hope all this hasn't affected that.
Write down any questions you have before you see the specialist, and also take pen and paper to make notes. When I was first diagnosed and saw the consultant, my head was so full of things that I struggled to remember everything they said.
Good luck