What Causes Severe Shoulder Pain And Dizziness?

Hi, I am a 45 year old female (height 5'8", weight 148 lbs) with significant hx of heart disease in my family. I have a severe pain running along the right shoulder blade (seems to be relieved a bit after taking Tylenol). Also become dizzy upon standing. Should I seek immediate medical attn or wait a bit and see how I feel?