the first marriage is presumed to be valid, and yours is void for being bigamous, and your husband can be prosecuted for bigamy. you also if you knew about the first marriage.
what is important is whether there is a valid ground for the first marriage to be annulled: http://www.pinoylawyer.org/t4792-grounds-for-annulment-declaration-of-nullity-legal-separation-and-separation-of-property
in my opinion, even if the first marriage is invalidated, yours will remain to be void, and they will always appear in the report of marriage/cenomar but with additional remarks if annulled.
regarding the birth certificate of the child, i hope you are not making it appear that you are the parents when you are not because that is the crime of simulation of birth.