Relationship/ Dating Advice

Hey everyone. Wanted to ask advice from those of you who have been or are in healthy, long relationships, especially anyone who is married.

Here goes:

I've been dating this incredible guy for some months now. I've been struggling because this is by far my most mature and serious relationship. I keep making mistakes like overreacting for little things and being too insecure. It took this relationship to show me all of my faults and my own immaturities that I'm working on as hard as I can.

My question is this: when you're in a relationship - how often is it okay to make mistakes? This relationship is a growing experience, I feel like I'm learning how I should be treated and loved for the first time. That being said, I keep making these mistakes- like being jealous for no reason, being too emotional, because I'm still learning how to grow out of that and be secure. But how often is too much? I'm afraid my inexperience and slow learning curve is going to scare him away. How much of a relationship is about making mistakes, especially if it's one person in particular?

As someone struggling to let go of perfectionism- I keep freaking out every time I say or do something that hurts him.