Cold sore or herpes inside my mouth. could it be either?

Same thing: Coldsore is the common name for herpes. However the sores may be due to other causes such as apthous ulcers and other conditions.

And some: There are many potential causes of oral mucosa ulcers (sores), including cold sores and herpes infection. However, there are other causes that may include contact allergy reaction, immunobullous disorders. A proper evaluation by a dermatologist is warranted.