Freezing when hit hard

I’m genuinely gutted so I fought in September and got caught with a flurry of punches and I clinched and came back but fuck me it was scary enough . So for some reason we only sparred now today since then as we do clinching all the time . I train 4 or 5 days a week. We sparred today and I was so nervous I got a big punch and I just froze and was throwing any random shot I could . I’ve practiced loads on pads and got my technique down well but I have a fight on the 29th of November and I’m genuinely nervous I’m going to suck badly . Is there a way to get loose . For context when I sparred a bit lighter I am far more fluid it’s just hard sparring and a fight that I genuinely go Into fight or flight once hit with punches I don’t mind getting kicked. Any advice would be greatly appreciated thank you