Is my ankle sprain healed enough for sports yet?

I sprained my ankle about 3 weeks ago and the pain is gone (walking down stairs, etc), and I've ran a little bit and there wasn't any pain. The only thing though, is that if I've been sitting down for a really long time and not using the foot, and especially waking up in the morning, when I start walking it hurts for a few seconds, then goes away after a few steps. Does this mean I'm not fully recovered/ready yet?