OK, so just to say up front that I know any advice from strangers on the internet is no substitute for proper medical advice but I'm on holiday and I can't stop worrying and last night I was wide awake for about 3 hours thinking about it and basically freaking out (it's weird how everything seems scarier at 4am).
So, here it is:
Last October I noticed a small pea-sized lump in my neck. Went to the doctor who said it was a lymph node that was enlarged because I have dermatitis on my scalp, which is sore and a bit red - so it was fighting an infection there.
They said not to worry but to come back if it didn't go away.
It didn't go away.
I went back in april to the doc who said it was probably still nothing but since it had been so long she wanted to confirm with her supervisor and would call me. She never did but I forgot about it a bit and life carried on.
It's still there. And I can feel another smaller lump further up near my hairline. Now, as soon as I am home I am going to go back to the doctor because here is what's worrying me - yes it's probably still just a reaction to my dermatitis BUT what if its not!? What if that is just coincidence and it means the doctors won't send me for tests because they think it's just that but actually it is something bad!? Would I have more symptoms? Or can it turn into something more sinister because it's been so long? You hear stories of people, especially young people, who have cancer but because it's so unlikely the doctor doesn't send them for tests until they have been back about 5 times!
I know someone who died from lymphoma after finding a lump in her neck when she was my age (mid-30s) and left her small children motherless. This is what's keeping me awake at night. I have 2 small children and would like a third. And I can't stop imagining what would happen if this was something more sinister. 
Someone please help me to get a grip! Am I being ridiculous? I am a worrier at the best of times and this keeps getting to me!