Chest Pain While Resting/Sleeping

Hello people.  It's been awhile for me.  Lately, I have been walking 2 - 2 1/2 miles a day 5 days a week, taking Vitamin D, E & Omga Fish Oil & Echinasea with Goldenseal.  I feel great!  But, I am finding that I wake up early in the morning with angina.  Sometimes wakes me from sleeping.  Doesn't bother me much while walking, but it's bad in the morning upon waking.  What's up with this?  Why doesn't this happen when walking? The angina goes away with 1 or 2 nitro and doesn't come back during the day.  

Thanks, Ally

[ChatterAlly]

Types of angina:

Variant Angina

The pain or discomfort:

Usually occurs at rest and during the night or early morning hours
Tends to be severe
Is relieved by angina medicine
Chest pain that lasts longer than a few minutes and is not relieved by rest or angina medicine may mean you are having—or are about to have—a heart attack. Call 911 right away.

Variant Angina
Causes:

Variant angina is caused by a spasm in a coronary artery. The spasm causes the walls of the artery to tighten. This narrows the artery, causing the blood flow to the heart to slow or stop. Variant angina may occur in people with and without CAD. Other causes of spasms in the arteries that supply the heart with blood are:

Exposure to cold
Emotional stress
Medications (vasoconstricting) that constrict or narrow blood vessels
Cigarette smoking

Maybe this is my answer.