Lots of bm

My son normally goes poop 1-2 times a day. On Wednesday he went eight times, yesterday he went 10 and he's already gone 4 today and it's not even 9 am. He had started acting uncomfortable, like his stomach hurts at times. This is a few pictures of what they've looked like.

He is 4 & a half more old and just formula fed- Enfamil Gentlease. He's never had any cereal or baby food.

His Dr said it could be a virus and he wasn't concerned yet.

What do you guys think?