I Have A Swelling On The Right Side, Just Above

I have a swelling on the right side, just above the collar noe at the bas of my neck. It's soft to touch. I'm 49, not on any medication. Just taking multi-vitamin. Experiencing "hot flashes," day and night. Exercise 4 times a week (Spinning twice, Dance class, and bodypump-strength training). Please advise........thank you