In my experience, a ‘good bottom’ is a skill that needs to be developed. I don’t know anybody that was a ‘good bottom’ on day one. Eager, maybe; nervous, certainly.
Yes, you should practice with the right toys, you should use enough lube and you should start slow and persevere when you and a buddy are going there.
A good top will read your body language. Will help you stretch before entering and will take it slow until you are comfortable before he starts hammering away, so to speak.
Now stop beating yourself up about it. It takes two to tango and a tango takes coordination (and a lot of practice). If he is a decent sort, he will brush it aside and be happy to help you practice!
I am 99% sure the 2nd time will be better and more fun - get back on the horse and have fun!