I say this with all courtesy - I am not sure if you are naive, or foolish,I presumed after the legal DNA result is provided, then the court and the parents boyfriend will want the costs of raising my child to this point paid back to the boyfriend as he paid everything to that point.
or if you are just over-thinking this whole thing.
You are not breaking new legal ground here.
It might be new to you, but it's a well trodden factual path.
I most strongly suggest that you take yourself to a Family Law lawyer, and
get yourself some properly thought out, case-specific, formal advice
about your obligations, and rights.
I further suggest that you do this without further delay,
lest you get yourself into a right mess.