Terminated after 20+ years for alcohol in UA

[lansshark]

I've been at my job 20+ years with zero medical errors, last week I forgot my purse at the gift shop, then got sick while at work then I was sent home, next day my supervisor kept calling my house wanting me to come in to get my purse and I told her that i was in bed sick and could not drive myself, after three days in bed sick I was able to go to work and get my purse, upon my arrival I was escorted thru the hospital by three police officers then they acted like they were going to arrest me but they didn't and after the UA they said I needed to call someone to drive me home because I didn't look very good ...NS..again I told them I had been in bed for the last 3 days. another three days went by and I received a call from my director telling me I was terminated because I failed my UA but she didn't know what had shown positive?? I couldn't understand this at all!! then I received a paper from her saying that alcohol showed in my UA! but I wasn't even supposed to be at work for another 72 hours when they made take the test! I had told them all the different medication I had taken, including Nyquil among others. Please advise if there is anything I can do! this is totally unfair.
thanks for any help in advance!