So from this last post of yours, I gather that you have not yet left the UK even though you were strongly advised to do so the last time you posted here seeking help. Also, I assume you haven't yet received any response concerning your FLR(M) application?
You do not have legal status in the UK and therefore you cannot get an NI number. Without an NI number, you cannot apply for child tax credits. Your husband is allowed to claim them because he is a UK citizen and has an NI number. However, if he has a spouse living with him, then that spouse must be included in benefits applications, even if s/he cannot claim in his or her own right. However, since you don't have legal status or an NI number, then any application that includes you will not be successful. See the problem?
Kalah, you really must go back to the US. I know it is not what you want, and that's perfectly understandable, but by staying you are only making things harder for yourself and for your husband and child. If you want a proper life in the UK, then you have to play by the rules.