Amazon pharmacy

I take name brand Lexapro every so often because I get to adjusted to the generic and it doesn’t work at its full potential. I switched all medications of mine to Amazon pharmacy and took my meds like normal last night, but I woke around 6am feeling weird and out of sorts and a boast of energy, and tingling all through my body then a weird rush and head pain. My heart rate keeps going all over the place and frankly it feels like a panic attack but not full blown. I have been on lexapro name brand and generic for 15 years, my question that I can only think of is Amazon pharmacy? And I’m curious if this has ever happened to anyone?