Went into court today for child support

i went into the friend of the courts office today for support for a hearing my ex husband said he made 28.95 a hour on a 40 hour pay week now my question is they would try and go by what i use to for my earnings 8 years ago but they wouldnt go by what he made 3 months ago i guess i dont understand that , i work a measly 45 hours every two weeks which i dont at the most maybe 50 but i usely work 45 wouldnt they have to go by his last wage . and he didnt even wanna give me child support when my son lives at my residence I NEED ANSWERS PLEASE HELP!!!