Well either that was bad peanut butter, but it's more likely crepes aren't good with peanut butter. The heat of the crepes might turn the peanut butter into oily glue, or in some cases gross clotted gorp. I used to try to put peanut butter on pancakes and it always turned out terrible (and I love peanut butter)

Peanut butter is much better with something that's a contrast like toast, crackers, crunchy veg - or blended into something like cookies, desserts, hot cereal, etc.