Are Continuous Heart Palpitations, Discomfort In The Neck, Sharp Pain Under My Left Arm And Discomfort Under My Clavicle Something Serious?

Hi,im an 18 year old and i have type 1 diabetes from age 11...my cholesterol level is 182mg/dL.I feel continuous heart palpitations accompanied with discomfort in the side of my neck and sharp pain under my left arm with discomfort under my clavicle.Is it serious or normal.Thanks.