Some may have that problem, yes. It's because the right-hand middle finger is used to typing the 'I' from QWERTY. However, the 'E' is also typed by middle fingers both in QWERTY and in Colemak and for a good reason: Since it's the most commonly typed letter it needs to be on a strong finger and not on an index finger (because these already cater to a bunch of other keys so you don't want to overwork them plus it'd lead to a bad case of same-finger digraph problems).

Shai first tried keeping the letter 'E' on the left hand in his now deprecated ASETION layout, but it didn't work well. So he improved it further, and Colemak was born.

You might want to do some exercises with lots of E and I in them to train up your motor memory if this bothers you. Or just let it be, relax and be happy and it'll get better. ;)

When I say "a few months", I only mean about 2 months. Well, actually only a month on my primary computer. Sorry, time seems to become distorted when I take up new interests! I suppose I am still early on in my learning. Still, I think I have almost reached QWERTY speeds, although they were not too good to start with.

Thanks for that. I have had a few problems with R and S, but generally only when typing "as". That's probably fairly common, isn't it?

I have experienced that the R-S problems was the hardest to re-learn and also that it somehow needs to be relearned in various states of mind. I still make the error when typing in an agitated state :-)