Check with your doctor as to what he will allow you to do. Just go easy with your karate until you get better. I have 3 herniated discs in my lower back, sciatic, spinal stenosis, just a really messed up lower back. Constant pain, it never stops. On 1 to 10 with 10 being the worst 0 being none the lowest the pain goes is about a 2. When it hits 5 and above, well it's pretty painful. Just keep a good outlook on life. You're young, the body can do amazing things as long as the mind is in a positive state. God bless.