I have sleep apnea only when I take a nap in afternoon& does not affect my normal sleep at night. Should I see a physician or just don't take naps?

Depends. this depends what you want to do with sleep apnea. if you do have significant sleep apnea, treatment often involves wearing a mask nightly or possible surgery in your pharynx, etc. If you are not prepared to do those things, I wouldn't get tested for apnea. Tip: sleeping on your stomach sometimes helps alleviates/resolves apnea. Also, if you are overweight, weight loss will help.