Strange enlarged vein running up from stomach to left side of chest

[mhsdrum]

Hello, and thank you all in advance for anything you can help with.  I am a 40 year old male, non smoker.

Yesterday I was taking a break from some computer work and stood up and stretched my arms upward, and noticed what appeared to be a bulging vein running from just above my navel all the way up to under my left chest (stops just under the nipple). It definitely has become tender to the touch, but is not visible unless I am stretching upward (arms above head, like a morning stretch). I do not have a history of DVT, and can think of no reason why this would have appeared. I should note, I had not been feeling well the prior 3-4 days before, and had been taking ibuprofen (anywhere from 600-800 mg) a couple times a day, and pseudoephedrine daily.

Does this sound like a thrombosed vein issue? It is odd because it runs up to the rib cage and then continues to be felt all the way to the chest/breast area, as though it is in front of the rib cage. I have scheduled an appointment with my primary care physician for the beginning of next week, but I do find it a concerning, and everything I read online (not much info exists) of course will scare the daylights out of me. I had seen a similar thing happen about 6 months ago up in the upper left chest shoulder area - a vein that I could visibly see pulsating, that was tender and firm to the touch, but it went away by the next morning.

Again, thank you for your help!