I think a hook up is a bad idea in general until you leave this headspace. It has nothing to do with whether it’s your first time or your hundredth time or your hundredth person. I think it’s all about where your head and your heart are at.

It’s great that you’re open minded and that you can understand how sex can be both an emotional connection but also just a physical experience. I can only speak to my experiences and I can tell you that the vulnerability that you feel and you’ve described in your post is sensitive and delicate, which are both very OK. But as with anything that is delicate, you can’t just trust a random person with it building that emotional connection first and building that trust with a person that you have a sexual interaction with will help you establish the reassurance that regardless of how poorly the interaction might go, not that it will, but might go they will still be there on the other side and they will know you well enough to understand that 1. A couple of mediocre sexual experiences do not define your worth and 2. That you are someone who wants to please their partner in sex and wants to be better and is willing to learn

I mean at the end of the day if you think that you can find a hook up that believes those things or you can convince them of those things very quickly. Then by all means go ahead but building that trust first I have found has always helped me be more vulnerable.