Look. It doesn't matter. People are going to get hurt in relationships. If there is no risk, there is no reward.

He is going to make mistakes in being the best BF for you possible. And if you ignore his mistakes because you don't want him to get hurt, he won't know he made mistakes. Which means he is going to repeat them with his next GF.

So as this is your first real relationship, it is likely it will fail eventually and you will both be moving on. You both have to offer each other some experiences and you can help each other to grow as a person.