Cold sores can be caused by an STD if you've been sexually active.
Your doctor can swab the cold sore to see if you do have an STD but mostly cold sores are nothing serious and just annoying.
Most cases of Herpes are caused by a virus called and known as the Herpes Simplex Virus.
Just because you do get a cold sore it doesn't mean you have an STD.
Many people who are never sexually active get cold sores so it doesn't mean that you have an STD when you have a cold sore.
Even kids who never have had sex will get cold sores.
You can apply some apple cider vinegar or hydrogen peroxide to your cold sore to help get rid of the cold sore.
Or even apply some toothpaste to the cold sore to get rid of it.
Most cold sores go away even on their own without treatment within 1 to 3 weeks.
People with STD do typically get more cold sores than those without an STD but you don't always have an STD with a cold sore.