You have no idea how much of a load it takes off of my shoulders to see that someone is experiencing nearly the exact same thing as me.
My dad recently died under extremely traumatic and graphic circumstances.
I moved into my cousins expecting stress relief and a solid place to stand so as to heal, but this was a mistake, the stress was made worse.
About a month later, I began having headaches in weird places, and paying extra attention to places of my body. I began to believe that I was in serious danger, and suspected aneurysm as the culprit. It moved from aneurysm to brain cancer as I was shocked to notice (something I had for awhile) cherry angioma on my chest. (red dots that occur mainly in the elderly but sometimes in the younger as well). I also had nausea mainly in the morning, but other times as well, and sometime during my stay I caught the flu.
I've had a bump under my chin for sometime, it is just as yours, small (pea sized), and slightly movable. I started believing it could be this, and that, and cancer, and hypertension.
I have never been a hypocondriact before in my life.
After reading the many posts here my mind has been put to ease, and seeing that you experience much similar symptoms, I can only tell you that from my experience it is stress.
My uncle is a doctor, and he checked me out, turns out I just need to get a little bit of sun exposure and look forward. Fearing death, and scouring the web and med books for answers to my problems isnt helping me get any more healthy.
Hope this post is a decent tribute to these forums, considering what they have given me, and I hope this post may help you a little.