Awaiting 2WW haematology referral

Hi,

i found a lump in my groin area around 7 weeks ago now, it's grown progressively and is now measuring 3.5cm. I feel nauseous a lot and have a raised fever randomly. 
My legs are extremely itchy even more so around my lump.

i went to see my GP a week ago, and was sent for an ultrasound, my lump grew so I went back to the GP as still not heard regarding the scan. I've now been referred for a 2WW urgent referral to the haematology clinic. 
 

im so worried and don't know what to expect at the first appointment, my blood tests show elevated ESR and CRP also, anyone know what happens at the first appointment as I have already had my bloods taken? 
 

thanks