Possibility of amendment to child support

My ex and I have one child together. We had a very messy separation. We went to court for custody, I wanted 50/50 and she wanted to keep him from me as much as possible.

She dragged the court process on for years with crazy tactics. She first claimed my father molested our son and so there was an investigation but her claims were never verified in any way. She then tried to move 4 hours away with him and that got denied. Then she spent the rest of the time fighting for me to have very limited time with him. All this to say that the process took a toll on me and broke me down mentally and emotionally and my time with my son was limited throughout. When we finally got to our settlement conference, she would only settle for 45/55% split parenting time over the year if I agreed to pay full child support and receive none of the child benefits from the government for him. I foolishly signed the agreement because I was exhausted and just wanted it to be over instead of going to trial, my priority at the time was just having a reasonable parenting schedule with my son. I was on legal aid at the time and it had run out because of her dragging out the process, and was pretty much pressured by my lawyer to sign.

It has been two years since our settlement and I cannot afford to keep paying full child support and receive no benefits while having my son nearly half the time and having all of the same expenses for him. We are stuck living in my parents small basement sharing a bed, while she has purchased a house, a new car, got engaged, and had a baby.

Last year I made 66k and she made 55k so I don't make much more than her, but having to pay now $600 a month and child support and receiving no benefits has kept us stuck where we are and we can't move on with our life, while she uses the support and benefits money to subsidize her life.

I need to know if it is even possible to go to court and amend the child support in our settlement agreement or if I will just be wasting my time and money and digging myself into a worse hole then I am. I've tried to reason with her and asked to change the amount to what child support usually looks like in cases of split parenting time but she refuses to budge and feels entitled to this money to be able to subsidize her life and to keep me down.