There are ruggers that are "littles" and "bigs" Each big gets a little to kinda look out for basically, it's a friendly thing My team has a get together where rookies are assigned "bigs"
Don't worry it's probably not offensive and you are very small to be playing expacialy wemens rugby I am small too only 5'2 and I'm one of the shortest on my team there was about 5 people around the same hight I play high school girls fall rugby so its girls ages 13-17