It's ok, we get it anyway. Actually, the little mistake draws the attention even more.
Yes, I have noticed how many anime character look the same. It's mind boggling sometimes. Even worse is when an artist has a similar style for all or most of their characters that are in the same anime program. This really makes it weird.
I have also noticed that some of the voice actors don't really change their voice that much for different shows. You know what I mean, your sitting there and you know the voice is familiar, and suddenly you realize it's the same voice as another character from a different show.
The whole thing is just somewhat unsettling sometimes. Especially when characters from different shows look exactly alike. It gets confusing.