Really anxious- lump in 4 year olds neck

Just over 2 weeks ago I discovered a lump in my sons neck, I took him to the GP who asked us to book a blood test, with it being bank holiday I called on the Monday and told had to wait 2 weeks so blood test booked in for next Tuesday.

 

we have our follow up with GP today, she said she was hoping the lump would be gone by now however it hasn’t and it’s still just as prominent if not bigger. It was 3cm 2 weeks ago and is not tender and not mobile, she is re measuring it today and checking him for any more lumps as he had another in his groin when she last checked. 

 

My mind is on overdrive and I cannot relax he has also lost 2lb of weight in the last 3 weeks although I’m not sure if his weight usually fluctuatates. He’s not unwell and the doctor said she was doing the blood test as there is no reason for the swollen lymph node, no cough, cold or illness since December last year. I’m really scared and I can’t sleep he is otherwise healthy