Hello TokenBoxTicker and welcome to the 'cabin' of PPRuNe.
That is a kind idea and I'm sure that Cabin Crew will be along in the next few days to answer you. It may well be that something given on departure is better. That said, offloading is always busy, so you might want to locate the senior cabin person (title varies by airline) during the flight and ask them to receive on behalf of all the cabin crew in your cabin.
The flight time is (typically) about 11.5 / 12.00 hours so there is a long period after the meal, when most of the cabin are sleeping or watching movies. This can be a good time to stretch your legs anyway. Also, it would depend if you are travelling with others.
May I reassure you that it is not embarrassing. A close friend of mine (South African as it happens) has flown long haul since childhood. But, for reasons unrelated to travel, they have become a nervous flyer and this happened when they were aged 41. It can happen to anyone.