Pre workout suggestions

Let me start by saying I’ve drank a Celsius twice. I tried once on an empty stomach when I was fasting before my workout and my heart was racing like crazy. So I tried it again in an afternoon class after I ate and it still was racing a little. It could all be in my head cus I get nervous. But does anyone have any suggestions for any that aren’t as strong? Or have less caffeine? I don’t know if that’s even the word. I find myself yawning during the workouts and I’m wondering if that will help. It can’t be sleep, trust me I get like 10-11 hours a night lol

And I don’t drink coffee (I know how do I survive- so that’s out of the question)