Turned down a fight offer 2 years ago, now regret it massively and coach won't bring it up again. How do I fix this without begging?

Hello, I have been doing kickboxing for over 5 years now. The day after getting my brown Belt 2 years ago. I was offered a fight by my coach, but I wasn't mentally ready and turned it down. Looking back, I regret it massively because I feel like I've wasted so much time.

​The problem is that my coach is an old-school type and never brought it up again since then. During regular training, he mostly ignores me and doesn't give much feedback, but during our hardcore Friday sparring sessions, he actually praises me. I know my skills are there now, but because of my past rejection and my stubborn ego, I really don't want to beg him.