Lumps under my neck,

[Chardri]

I have two elongated lumps under my neck, on the inside of each sternocleidomastoid muscle, starting from the angle of my jaw mandible and extending downwards, about an inch and a half. Possible the carotid sinus area? (I'm trying to describe them through anatomy photos attained from google images). They are both about the same size but very large, although they are hard to see. They are moveable and when I feel them I can feel my heart beat quite prominently. They also get a bit tender if I touch them a lot. I've had them for a while and they seem to grow and shrink slightly at times. I am a little worried as to what they are and I'm pretty sure they're not lymph nodes.

I do have issues with my sinuses which I utilise steam to help clear.
I'm male mid 20's
No other diagnosed conditions.
I don't smoke but I do vape.

I'm so sorry if I've made a mess of trying to describe them, I've googled extensively and cannot seem to find anything which matches what I have.