can I ask 1 question, split into three parts?

I was in ICU for a heart attack during Xmas, released, prescribed Xanax, which I had taken before with no issues,5 days after my release, I had heartburn and stuffy nose,for which I took Tagamet and Benadryl, also 1mg of Xanax for anxiety. I passed out in a Walmart,was arrested for pubic intoxication and resisting arrest.I have no memory of this event,what so ever.I was not drinking,I have no history of drug abuse and work in the nuclear field. Speaking with pharmacists, they say those meds react with each other.I did not know this before mixing,having another heart attack was my main worry.I need to fight this case,it will cause me to lose my job if convicted,do I stand a chance?