As previously mentioned--I have a small member (to avoid more vulgar words such as dick, cock, meat rod, etc.)
I have been with a few girls..Most of whom the first sexual encounter was one of passion during which they never saw it first. They never knew it was small until after it gave them a seizuregasm. They never had a problem getting off during subsequent encounters.
So no, physically, it doesn"t matter. If a woman has the idea that it wont satisfy them, however, it won"t. This is psychological.