Well, you are treating the injury but not the cause. There is something in your movement or perhaps in your body (hips, back etc) that is not aligned or being loaded correctly causing you to injure yourself.
If you play other sports where you kick with your dominate foot a lot. You probably developed stability on your left leg, more so that your right. Now that you are kicking with the left and using the right for stability, it might not be up for the task...just a thought.
No way to know over the net but a good sports therapist could evaluate you out in a few minutes and likely figure it out.
The danger of self diagnosis or asking just anyone is if you compensate, good chance you make it worse and add a new nagging injury...just not worth it.
Undefeated in all of Asia!