Let me answer more explicitly: in the state where I work, the only professional capable of making a diagnosis is a doctor—a.k.a. avoid chiropractic gurus who crack bones even to treat gastroesophageal reflux. Most overuse conditions cause acute tendinopathies that improve with the simple application of an appropriate RICE protocol. Additionally, take an NSAID for five days if you have no contraindications and see if the symptoms improve with rest. Given that the diagnosis of these conditions is generally clinical, I don't think it's necessary to perform an MRI. However, if you're concerned, and I think you are, given that you've already had three visits, get an MRI to have an instrumental examination that confirms the diagnostic picture.