I've tweaked my ankle a month ago, it doesn't hurt but is still kinda swollen, what does this mean?

Healing : This sounds like you had a sprain. Depending on how bad the sprain was, it will take a longer time to heal. Be patient and avoid aggravating activities.

Continued injury: I would try wearing a support stocking to help force out the swelling.

YOU may have: irritated the ligaments and you continues to walk and so how would they get better?