How to convince my mom i'm not cut out to be a lifeguard?

My mom wants me to finish my lifeguarding this summer and to do that i have to p 2-3 courses (W.S.I., NLS Pool and NLS waterpark) which would take 2 and a half weeks (1 week for the first 2, half a week for the waterpark) IF I P THEM ALL IN ONE SHOT. Last summer i took 5 courses; the 3 aforementioned, plus a redo of the NLS pool and a renewal on my standard first aid, since it had expired. out of all the courses, i only ped the first aid renewal (i technically ped the waterpark, but since i failed my pool i wasn't eligible to p. The last time i even set foot in a pool was almost a year ago, the last day of my last course (which i failed). Honesly, i'm not the greatest swimmer, i never really spent alot of time at the pool actually doing strokes and stuff. my mom just wants me to finish it because it looks good on a resume and you can get paid $20 an hour. while it does seem great to have that kind of money and something like that on a resume, i dont think im cut out. i struggle when im doing the courses and all it's doing is hacking away at my confidence and self esteem and even if i do p, getting the actual job would be extremely difficult with all the competition out there. i don't think i could be someone who saves someones life, i would be the guy who freezes up and then goes into insanity because the person died. please help, she won't llisten, all she says is "it looks great on a resume it's $20 dollars an hour and i'm willing to pay for it"