Honestly, unless it's really hot where you are and/or you sweat super heavily, I don't think you need to worry about electrolytes at this point. That's more of an issue as you get into hard rides of 2 hours or more. I'd expect your cramps were more from unaccustomed use of the muscles, and they'll lessen as you keep getting stronger.

Regardless, congrats on the progress! It's great to see you having so much fun.