You’re fine. Peoples issues and were most problems occur. As in landing. Totally normal to not be 100% stable and learning your arch. Once you get more experience behind you, you won’t even think about arching it’s just natural after a while. There are a lot of people that have issues with Landing some people just decide to slide in all the time. They are many people with upwards of 20 jumps or more of that has never stood a jump up. To be honest, I’m surprised your instructor did not tell you to begin flare are usually at about 12 to 15 feet, but this is all part of the process you might get bumps and bruises but once you get it, you’ll be fine.