Say that again?

In my other life I was a teacher. Days of yore spent teaching children how to read, write, and develop a love of math. (ha!)  Now fast forward to my current life where I have just one student and the pressure is to teach greater than when I was at a private school!  I had always thought that language acquisition was a skill that just naturally came to us as we are surrounded by a world that is rich in vocabulary.  When my students came to me, they knew how to speak,yet not always properly (lie-berry for library still kills me) but grasping the basic skills of conversation.  
We are working on raising a bilingual child, whereas I am thinking it may border a third installment of language called gibberish.  For a long while now he has been stuck on monosyllabic sounds and a constant sound of mmmm; that the pitch of which is determined by his ever fluctuating moods.  So, here I am with an 11 month old trying desperately to get him to say 'mama' and he looks me square in the face and beams at me as he says 'dada'! Argh another knife in the gut and more points for the daddy side.  I know that he is learning words from us, hopefully not the kind that I tend to speak whilst driving, as he is recognizing the words that I say.  Is it too early to start spelling?  I cannot ask if my husband wants a glass of milk or I will get the mmmmm sound of the demanding sort.  And those little dissolveable puffs in the plastic containers? He is NUTS for them and even if he just ate a full lunch will freak out if you ask him if he wants some puffs.  Now that I know that he understands the words I am saying, how the hell do I get on the same page?  A couple weeks ago I was taking him up for his bath and I know he repeated the word 'baa' back to me, wherein I totally got excited and finally felt that I had gotten through and that we could finally discuss in depth these late night crying fits.  Did he say it again? As that is the test of understanding a concept.  Sure, he said baa again but this time it was when he wanted to go outside. Wrong context. Of course the mother AND the teacher in me are sliding into our overcoat of guilt in thinking that maybe we aren't practicing enough, maybe there is a problem (definitely not!), do I need to create more diverse lesson plans? Sometimes I get on the internet to see what the land of google thinks about certain topics of parenting, but I have learned not to take these pages as doctrine.  I am happy to say that the books we read, my constant gabbing to my son, and games we play are setting him up to be quite the motormouth, as soon as I can understand what he is saying. 
All and all his language acquisition is really blooming.  Even as the past week has gone on, more sounds or shall I say words are starting to form, as well as a fun pterodactyl sound that he likes to emit when I tell him no.