I noticed a white/skin color mark(bit like a tear) on my glans penis foreskin 2 or 3 months ago.its still the same no pain, itching.something serious?

Color: I cannot think of anything of consequence that it could be.You may have caused a minor contusion and it should eventually disappear. Good Luck

You need STD testing: If you have been sexually active in the last year you need to be tested for STD's. You should be tested for all STDs: HIV, Hep C, Gonorrhea, chlamydia, but especially syphilis which cause non-painful lesions like you describe. It requires a blood test. There are a few; RPR and VDRL are the most common tests for syphilis. If not that you can explore other causes such as a fungal infection.