Thanks for posting OP. So easy to put off seeing the GP is you aren't sure there really is something wrong. Especially in the times of coronavirus.
My son has T1 and the symptoms came on slowly and got gradually more obvious.
I knew something was different about him but because he'd didn't wasn't sick, didn't have temp or a rash I didn't think it was serious. It was my mum who realised what it was.
Previous poster, as others have said, get your child checked today, hopefully he is OK. Thinking of you today.