George, you mentioned "slurring of the speech". Sounds like Bell's Palsy to me, I should know, been there, done that.
Back in '04, I had that and lost total control of the right side of my face, including half my lips. I couldn't eat anything, so was subsisting on milkshakes with a straw.
Went to several doctors, mainly neurology types, ( CAT scans, MRI's etc ) no diagnosis other than the palsy.
Bottom line, I went into a coma and was rushed to the hospital, I had a blood glucose reading of over 800.
I stayed in the hospital 4 days on an insulin drip, and have been taking 2 daily insulin injections since.
Seems none of my doctors could diagnose type 1 diabetes.

Go get you one of those cheap, or free blood glucose meters from a drug store.
Take readings at least 3 times a day morning, noon and night for 3 or 4 days.
If any reading is under 60 or over 250, you have major cause for concern.

85 - 95 is the 'ideal'.