Changed feeding schedule

Joanna • instagram/facebook:yanncandy
My baby all of a sudden started breastfeeding less minutes than how he used to and more often. Like, he was eating every 2 1/2 hrs for 20minutes each time-- now every 1 1/2 hrs for 3-10 minutes. Then he falls asleep while eating in my lap and on my boobs. Is that something worrying ?