After 3 years my babymama told me my son wasn't mine after she went and filed for child support and got it nobody said anything about a dna test when this all took place not the judge or the lady at the child support office at the court house and now when I ask them about getting a dna test they just give me the run around and keep referring me to this one lawyer who wants 1,500 up front witch I don't have 1,500 is their anyway the state could help me get a dna test

I suspect that you signed an acknowledgement of paternity at some point. And having done so, according to state law you are the legal father and it may be that in your state, the window to challenge paternity has passed. So even if a test shows you are not the father, you are stuck.

Without knowing where you are we don't know what laws apply.