Go to the dr.! Please. . . My husband (very fit cyclist, thin, etc, but with a horrible family history) had similiar symptoms a year and a half ago. He got the blood pressure and cholesterol fixed with meds, but kept having symptoms even though NOTHING showed up on the myo-view, the non-invasive test used to check for blockages. Finally when i started climbing the hills faster and the pain was getting worse at less and less intensity levels he practically forced them to schedule an angiogram. He had 2 80% blockages and had 2 stents put in. If he hadn't pushed the issue he would have been one of those guys who dropped dead shoveling snow.
Even if you have something like this, being a cyclist will help. He was walking 2 miles 2 days after surgery and was on his bike after 5 days.