Hi! I wouldn't worry about healing etc I have recently had a lot of work done just make sure you have plenty of bepanthem, cling film and micro pourus tape to keep it covered for the first few days.
My only other comment is make sure what you get is right for you. I have a few tattoos some I still like others I don't. My worry about a diabetes tattoo is that I'm not sure it's recognised as a medical alert and I personally wouldn't want something on me drawing attention to the fact I have diabetes as I don't think it's a defining feature.
But each to there own! Good luck!
My only other comment is make sure what you get is right for you. I have a few tattoos some I still like others I don't. My worry about a diabetes tattoo is that I'm not sure it's recognised as a medical alert and I personally wouldn't want something on me drawing attention to the fact I have diabetes as I don't think it's a defining feature.
But each to there own! Good luck!