Std question

I have recently found out that you can contract herpes without having any symptoms, for years even. Does anyone know how common this is? My ex and I have been broken up for about 3 years and he cheated on me several times throughout our 2 year long relationship. Now I am paranoid that I could have gotten it and not even know that he had it or gave it to me. I think now I am pregnant I am super worrisome.