Swollen lymph nodes

Hi, 

i was wondering if anyone could shed a little light if they have been in this situation. I recently discovered a lump in the back of my neck upon further investigation I found a raised lymph node in my armpit. My blood are all clear and my doctor suggested glandular fever. I can't even remember the last time I was unwell so I don't feel it could be that. The blood test detected EBV consistent with a previous infection. It's been three weeks and the lump is still there and my lymph node is still swollen. My mum has non-Hodgkin lymphoma so I feel extra worried. I'm anxioua the doctor is just going to rule it off as glandular fever. Should I push for further investigations?