Congrats, Jono. I'm late to the party here, but don't get too worried about pushing the exercise too early. Dr. Gross has his patients do only the following for the first two weeks:
Foot pumps (to help prevent clotting) 3-4x per day.
Heel slides, 2 sets of 10 per day. (While laying on your back, slide your heel towards your buttocks on the operated side).
Clamshell: On your back with both knees bent, open your knees to a comfortable amount, and return together.
Walking: Up to one mile.
After six weeks, he adds leg lifts to this, plus allows walking as much as you want.
At 4 months I went to PT, and - for me - one of the BEST exercises that helped "tighten up" the hip capsule was this: On your back, bring your heels together and towards your butt, so your knees are up. keeping your feet in place, lift you pelvis up until your thighs and torso are straight, and hold for a count of five.
I wouldn't do that at two weeks, though. Does your surgeon suggest PT?