I carried a small Black Diamond headlamp that I could hang around my neck and wear to bed. It was then easy to find if I needed to visit the toilet after lights out. A small hand torch would have worked as well otherwise, but if you have to rattle around finding it, you might be at risk of waking your neighbours in the dormitory.
As a technique, I never wore it on my head, but left it hanging in front of me pointing towards the floor. You might be surprized how much you move your head around, with the attendant risk that you will shine it all over the dormitory. You torso moves much less.
Red preserves one's night adapted vision, which you will destroy if you then turn on the lights in the shower/toilet etc. So if you do take a red torch, the trick is to either learn to close one eye when you are in white light, or just use the red light. Not as easy as it sounds, but not impossible.
As for walking in the dark, I am with Anniesantiago on that issue. Civil twilight will start around 0715 in September, a bit earlier the further east you are and later as the month progresses. If you are really keen, nautical twilight is even earlier. It is possible to walk at nautical twilight, but shapes on the ground will still be seen as general outlines, and not in any detail. Getting away earlier is possible, but you make no friends with a noisy early departure.
Regards,