18 months can only say few words

My child will be 18 months this week ,18 month check up is next week

My concern is if it’s normal that my child doesn’t say a lot of words at this time

Words I have noticed is only girl , mom, daddy ,cup & mhmmmm lol & I think he says good lol

A lot of times he is talking to me but I really don’t understand what he is saying so I respond back like I know lol and he is very smart if I ask him to go get his cup he go find it & bring it to me , if I tell him to bring me his socks he will , he doesn’t show any signs of autism or anything but of course I’m not a doctor . he pays attention he knows so far where is nose and mouth is and he plays with other kids and everything