Hi Leesa. My DD wasn't early (was born at 41 weeks) but I think at 2 she probably had a similar amount of words. Her first word was 'bye' at about 13 months, but after that she really didn't say a whole lot until she was a couple of months past her 2nd birthday. Even then, it wasn't clear to other people. Now she is 3, I feel her speech is quite good and sort of on par with her peers, but many of them were speaking far more clearly than her at 2.
Having said that, you could always chat to your MCHN about it - I have been given some exercises from my MCHN for some of Natty's pronunciation issues. Sometimes they can be helpful people, LOL!