SSA and me

I talked to ssa 2 days ago, and basically found out I am on SSDI, my social security disability insurance, this is the thing you pay into for social security while you are employed. It has nothing to do with other peoples money. So the associate told me I have enough left to pay me SSDI till october 2018, and also I do not qualify for SSI, that I am on some sorta program that does test runs for getting a job. How can i not qualify for SSI, i have an illness that without my medication I would be asleep all the time. My medication does not keep me awake. It keeps me barely functional. Also