I Am 17 Year Old Boy And Started Masturbating To

I am 17 year old boy and started masturbating to porn since 1.5 yrs earlier.. I used to have orgasm everytime I masturbated before ( intially 1-2 times per week and recently daily once) but since last 2-3 weeks I dont get orgasm after ejaculation as before. I am woried. Have I made a permanent damage? Is there any casue without any medication as such? in terms of stress, a little more stressful days lately because of high studies. Please do reply.