Yeah, maybe it is a little odd to ask for more space at this stage of things, but if it's what you need to move forward, there's nothing wrong with it. Everyone is different... and feeling suffocated or trapped once you commit isn't that unusual.

Your history probably contributes to this as well, but it's what you both have to work with. It's not so much something is wrong with you but this is a challenge you both have to overcome or work around to move forward with the relationship.