I suggest for your first tattoo not goin balls out on a huge side piece bc you dont know how youll handle it. Sometimes the pain isnt what gets to people but the lying in the same position for 6+ hours can take a toll on you.
EDIT: btw good choice, i have a koi on my arm. Its like 8"x6" and bc of the detail it took 3 hours. A piece on your whole side will likely be bigger than that and may take multiple sessions. Which is alot of time and money lol