as above really, yourve done the 3 game rule etc, it sounds like you have, if so then your fine anyway and its just a paper filling in exercise with stamps etc. and a formality, to avoid any issues, maybe just follow the processes involved, speak to the retailer about your membership and go from there, you never know
on another note, make sure it is really what you want to do, maybe a few games borrowing one to see, be a shame to waste the money if you don't like it after a few games?.....can always sell it on here