i tried reading cards for friends for awhile.
pne friend was so impressed that she wanted to set up a booth for me so "we" could make money for my readings.
while extra money for "us" sounded good, i had to tell her that my energy was exhausted after each reading for one person, and i doubted i could even do two in one day.
also when doing healing candles i would become exhausted after the first day.
i was advised by a friend who knows and i trust, to put my name at the top of a candle designed for multiple people to heal.
it worked ok, but still tired.
so i was then told that when doing healing work, i may have to put a separate candle for my self and whoever else the energy deficit might involve.
that works better. even put my candle in a separate room.
so, i know how energy work can drain you.
in addition to grounding after a spell, you may want to do an energy protection bath for yourself before and after a spell of that magnitude.
also, ask the powers or deities to allow only the desired or enough energy into the spell so that you do not overdo it.
that is a very amusingly good analogy about hangover.
when using alcoholic beverages, presumably the more you drink the worse the hangover i guess.
so you might want to investigate exactly what is needed for the spell and use precautions not to overdo. sometimes more is better, and sometimes not.
some people think that the dose of two aspirins is good, then three is better. with aspirin, three does nothing except waste an aspirin. so it sounds like you are capable of a lot of power raising and that is good for spells.
not so good if you use more than is needed.
so, again i say you might so a self spell before or light a perpetual candle for yourself in the name of energy use for spells.
bathe for the spell and after.
could work for you.