Do K cramps feel like a heart attack?

Sweating profusely , heavy breathing , whole body vibrating, muscles in hands seizing and hands closing up involuntarily, intense pain deep in chest and back.

It was insane, I had a co worker phone an ambulance but cancelled it when I came out of it, lasted about 20 minutes.

Obv I'm totally done with k now since this happened after sniffing a Q over the weekend but I was just wondering if it could have been something more serious. I can still feel my heart beat all the time. I have a doc appointment on thu , just kinda worried.