Really both babies are doing this, but one more than the other. They are suddenly wanting to nurse for long periods of time (an hour or more) and more often (all through the night when they were previously sleeping for 7 hours at a stretch). My nipples are very sore (like they feel bruised). I did actually feel one baby chomping on my nipples with her gums. They are suddenly chewing on their fingers constantly and drooling while they do this (preferring their fingers to nursing or even a pacie many times). If I put my finger in their mouths they chomp on it, rather than suck.
I haven't noticed a change in stools except maybe they are more watery.
They are both 3 1/2. I cut my first tooth at 3 months so that is why I wondered.
I had thought it could be a growth spurt, but wasn't sure.
It sounds like teething to me. However, ds was showing classic signs of teething starting around 3-4 months, but didn't cut his first tooth until he was 8.5 months, so I don't know if it was really teething or not. Ds never had this, but I do believe that watery stools are a sign of teething.