Because your statement says you have enough credits for Medicare at age 65, you have enough credits now. With Medicare you only have to have earned enough credits during your lifetime. For Social Security Disability, you need to have earned enough credits in the not too distant past. The number of credits you need depends on your age. See the chart in the SSA booklet How You Earn Credits:
The Social Security "blue book" lists dialysis and transplant under "genito-urinary" (Section 6.00). At Stage 4, whether SSA would find you disabled would depend on your labs, symptoms, etc. It's likely that SSA would ask for medical records from your doctors and it's possible that they may want you to see one of their doctors. When you have kidney failure and are on dialysis, SSA accepts that form (CMS 2728) as proof of kidney failure.
Social Security accepts and processes Medicare applications. Medicaid applications are processed by the state agency which is called different things in different states. You could look up your state's Medicaid agency here:
You could contact your state VR agency and see if they'll help you. The worst they can say is that you don't meet one of their eligibility criteria now, which means you may meet their eligibility criteria later.
BTW, when you start dialysis, there will be a social worker and a dietitian in addition to the nurses, technicians, and physician(s) that will work with you to help you stay as healthy and active as possible.