Re: Hand Foot and Mouth Problems
I think it sounds like a strike to me. We had plenty of them after the age of 1 and it was always illness related.
Could have gotten worse in his mouth, or the sores in there are probably very painful. It's very common for them to strike with this particular illness, there have been many threads about it.
At 18 months you don't have to worry about your supply. Just hand express or pump if engorged, and offer the breast but don't push. Once he feels better he will certainly come back to it.
Hang in there! Before you know it he will be back as your nursling.