<human>: The background: In January of 2015, I was diagnosed with Type 1 diabetes. I was close to DKA (diabetic ketoacidosis, a.k.a. diabetic coma) when I entered the ER (blood glucose was 600, A1c was 14)*, and thus had to take some significant time off of work. Since then, I've had to continue to take off more time for related illness and doctor's appointments.

The job: I currently work at a small non-profit organization in the United States (Illinois). There are only 6 employees, including my boss (CEO/Executive Director). In a given calendar year (January 1 - December 31), we are allotted 15 "personal days". These days are not differentiated (i.e. there is no difference between sick days, vacation days, bereavement days, etc.), and there is currently no company-wide policy on what happens if someone uses all of their "personal days". Furthermore, we have no short term disability policy.

As of writing this, I have taken off 14 of my 15 "personal days".

The situation: A short time ago, my boss approached me with a document that alters my working schedule based on the amount of time I have taken off thus far. It gives me 5 additional (unpaid) days off, but prevents me from receiving a raise or promotion until January 2016 (when my "personal days" would renew). Additionally, if I use the 5 unpaid days off before the end of the year (December 31), I will be forced to move to part-time (4 days a week, 30 hours a week, with a 20% pay cut), but will still retain my health insurance.

I have been told verbally (I have a recording of this conversation) that this agreement only applies to me. However, my boss has refused to clarify exactly why, in writing or verbally, this only applies to me (also have on recording). See the document in the link below.

The question: Is this discrimination? I don't really understand the legal stuff around this and would love some insight. Any and all advice is welcome.

Summarize the given text in a few sentences.
<bot>: After getting diagnosed with Type 1 diabetes in January 2015, my boss changed my employment contract in what may be a discriminatory way. Looking for advice!