Second Opinion?!

Second Opinion?

For over 5 months I have had a lump under my jawline on the left side. I have already had glandular Fever so its not that.
I have also been feeling tired, sick, getting headaches and pains in the stomach. I recently went to the doctors for more blood tests. He said there was nothing wrong with me.
Does Lymphoma show up in blood tests and should I go and see a different doctor because I am pretty sure that something is wrong!
Thanks

The definition of an enlarged lymph node is size larger than one centimeter (0.4 inch) in diameter. Pea-size lymph nodes are not enlarged, even if you didn't feel them there before. Any node that is larger than 1cm in diameter should be followed closely by a physician. It should shrink noticeably within 4-6 weeks, and should be less than one centimeter within 8-12 weeks. High-risk enlarged nodes are those larger than 3cm (more than an inch) in diameter.

I have also heard if you palpate lymph nodes frequently, if they are enlarged, they don't shrink as fast. And that exercise helps your lymph nodes filter and remove any harmful substances and infection more efficiently, thus helping them go back to normal faster.