Feeling of instability or popping of knee while doing activity or at rest should not be taken lightly. it signifies some internal derangement of the knee. because of the inherent unstable nature of the knee joint and its vulnerability to trauma, the soft tissues like ligaments of the knee joint gets torn resulting in instability and if not properly treated can result in chronic instability. the tear can be very partial to complete tears.
in your case it looks like that tear is minimal and all that is needed is bracing
of knee joint for 6 weeks. but exact nature of the injury
can only be seen with MRI
. so it is advisable to consult orthopedic surgeon and let him decide.