[cobramania]

Oz, I did the exact same thing as you, missed a step & rolled my left ankle bad, 4 weeks before last Christmas, while helping a mate out at work, (not employed by him so no compo). After getting up off the ground about 15 mins later, I stayed at work & walked around tentatively & in pain for a few hours, before going to the A&E, (I had basketball style work boots on, so had good ankle support at the time).

Had X-ray, no breaks, but ligament damage. I was told to stay off it for 48 hours using R.I.C.E. Treatment, then use it as much as possible. Should repair itself in 7-8 weeks.
I couldn't walk on it without using a walking stick for 2 weeks, & was still hobbling around on Christmas day.

Just after New Years I twisted around in bare feet & strained it again, went & got another X-ray, still no break. I was put into intensive physio program 3 days per week for 5 weeks.

The first week was physio to help repair & get the swelling down. The next 4 weeks were to strengthen the ankle, apparently this is very very important, otherwise the ankle will be weak for the rest of your life, & you'll roll it again very easily.
3 months later almost to the day, I now have full use back in it, with very slight pain if I stretch it to the limits.
Within another 6 weeks I expect to have no more pain, with full use & strength back, with no greater risk of damaging it again than if it never happened in the first place.

I'd be getting into physio. as soon as possible if I were you, the ligament will repair eventually, but if you don't get the strength back in the fibres, you're screwed.