Knee injury from surfing

Hi,
i’m wondering if someone can help me identify the name of the injury to my knee.
it was a minor event when i was surfing last week, i straightened out my leg while it was toed out. felt the knee cap or some ligament rolled over my knee, and then it rolled back into place when i took weight off it. It was not dramatic, but it hurt a little. i’ve been icing it and surfing since. i feel pain when i walk up or down stairs. (and not at any other time) the pain seems focused in front of inside of knee. and some tightness from behind knee early in morning.
can still surf, but i’m scared about injuring it further, want to start strengthening exercises but do not know the name of this injury, so am not sure what exercises are appropriate for this type of minor injury yet.
if you have any ideas please let me know. i’ve looked through the list and the closest thing i’ve found is patellofemoral pain syndrome, but how i acquired the injury does not fit with the profile of this type of injury.

thanks,
aimee