Welcome to THR.
First time at the range is all about safety (four rules, proper gun handling, etc.). If no one's dead, you did superb. As for the groups, a sub-compact will be a bit harder to shoot accurately due to the lack of a full grip. Also, the .45 caliber has a decent amount of recoil to it. Ideally, a first timer should shoot a fullsized gun in a smaller caliber (9mm, maybe even .22) to get the proper techniques down. That said, those groups are great for your first time! More experienced shooters, however, can shoot coin-sized groups at those distances.
Did a more experienced shooter bring you? If so, did that person teach you the basics of sight picture, trigger control, grip, stance, breathing, etc.? If not, you need to start there.
Usually, pulled shots come from a flinch, which is a result of expectation of recoil. One of the best ways to get rid of a flinch is dry firing (pulling the trigger on an empty gun or a gun loaded with dummy rounds). Another is to shoot guns w/ little to no recoil (.22's).
Good luck. Learn proper form now, as you prolly don't have too many bad habits to unlearn yet. It'll be a fun journey, guaranteed!
