Tim Hortons

This evening on my lunch break, I grabbed my vanilla latte as I usually would.
The interaction was strange, the prioce went from $3.45 yesterday, to $3.65 this time.
Strange, but I debited and moved along.
I noticed almost immediately as I drove that the drink was not correct.
Upon arriving back at work, I found the cup to be a white liquid with a vanilla sweetener added to it. Unsure what the drink is.
I called the location, they answered without identifying themselves or the business, they then pretended not to be tim hortons.
I confirmed the address and she admitted that yes, she was tim hortons. She then stated that she hadn't served a vanilla latte in the last hour.
I reminded her of our price conversation and she admitted that maybe she had made it.
She would not tell me what I ingested and said 'too bad, talk to manager in the morning"
I saved the liquid and cup, I also know I attended at 10:54-10:57pm and my car is onj camera showing this, as well as my debit receipt will be on m,y account.
At this moment, I believe I was maybe over charged, and have ingested a liquid that I do not know is in it.
I want to know what I drank, and why the staff were in such denial and offered no resolve.
I am feeling ill and am unsure of how to proceed.