DS1 is 22 months at end of the month. He was born at 37+5 by emcs due to reduced movement. He was very alert and responsive at birth and I had him with me for the first night in hospital. He had trouble feeding and a midwife wanted to check his blood sugars which ended up being unreadable as they were so low. He spent 16 days in SCBU being treated for his low blood sugars and all was well and he came home.
He generally hit most milestones to do with fine motor skills and babbled lots but crawled fairly late at 13m and walked at 17m, there's been no stopping him since 
However it's his speech me and DH are starting to worry about. He says mama dada baba but not really to me, his dad or his little brother. He constantly chats to himself and us making lots of different sounds and intimations, if he watches a video of himself saying mama dada he will copy it and most of the time will copy us saying it but that's it. He won't copy other words.
He understands a few simple commands like "get your drink", "give (brothers name) his drink", "where is daddy?" etc.
He also is very observant and copies things we do like wiping things up or cooking (he copies with his toy kitchen and food).
What should we do next? I don't want to leave it til his 2-2.5year check.
If it makes any difference he has very waxy ears and hates having them cleaned, any tips there?