Hi Sarahhenry.  Welcome to the forum.

I'm not a doctor and I have no medical qualifications, however questions similar to this get posted regularly.

As I'm sure you know, lymph nodes pop up in response to an infection (reactive) - when this happens sometimes they hurt and sometimes they don't.  Once it pops up, a node can stay swollen for several weeks as it fights the infection, and should normally shrink back to normal - although some never do.  The last time I checked the advice was to see a GP if a node remains swollen for more than 4-6 weeks.

In my personal experience, nodes can and do pop up with me not being aware of any infection, so I think it's quite possible your nodes are reactive (normal) and your body is fighting an infection without you being aware of it. That could also be the reason for the small temperature increase you mentioned. 

I also note you make no mention of the so-called "B" symptoms that often (but not always) accompany lymphoma.  Of these, drenching night sweats is the most obvious, but there can also be severe itching, fatigue, unexplained weight loss and few others. 

I know it's difficult but I would try not to panic. There doesn't seem any particular reason to think of cancer.