I woke up with a swollen lymph node on the back left side of my neck. Quite sore and slightly painful?

Monitoring Centers. Lymphatic system absorbs/carries things too big to go into the arteries/veins like bacteria eaten by white cells and digested food. Lymph nodes "taste" the lymph for anything bad like bacteria/viruses/cancers, etc. When it detects a problem, it alerts the immune system and your body reacts. They enlarge in response to the inflammation they create when they react. They shrink when all is well.
Our filters. Lymph nodes are our filters to take organisms (bacteria, viruses, etc) out of our bloodstream. Most common reason for a swollen lymph node is infection. Especially if it is sore and swollen, it is more likely to be secondary to infection or inflammation (it can also swell in association with allergies).
Maybe lymphadenitis. You should get seen and you may need an antibiotic for 'lymphadenitis' (a common condition of infected lymph node).

Related Questions

How to tell when a lump in the neck is a swollen lymph node or something else? My lump is not sore either. On left side only!

Get examined. I believe these are reactive or benign reactions to your previous story of runny nose but since it is low on neck and on left, have a clinic doc examine that for you. The definite way to tell noninvasively is by radiologic imaging or even a biopsy But those procedures are only planned if your clinic doc saw your person, evaluated your lump and decides. We can not tell by just reading your notes. Read more...

Is it normal to have a sore neck with a swollen lymph node?

Depends. Not normal if persistent or if the pain or swelling gets worse. If symptoms prolonged to consult your doctor. Read more...

I have swollen lymph node on neck by Adam's apple for months, I guess another on upper arm and another I guess high back neck. All left side. Not sick?

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