Neck dissection. Post surgery

Hi.

I am one week post surgery following neck dissection to remove some lymph nodes. This was to see if there was any cancer cells present following the removal of a small cancer on my tongue 5 weeks ago.

i was told there would be some swelling, but I look like I’ve swallowed a balloon. It is also very tender to touch.

my scar goes in an arc from my ear down across the front of my neck. I am not seeing the doctor for another week.

my question is, how do I tell if it’s swelling or lymphoedema?

thank you