Baby babbling

My son is 6 months two weeks he is not yet babbling consonants. "Ba ba ba" he is however screetching and blowing raspberries. Some oohs ahhs and eees. My doctor referred us to early intervention .. which I have followed thru with since I'm terrified. Second time Mom's or even Mom's now.. when did this happen for you? I am googling myself into a huge all of anxiety. I am so nervous.