35 year old, looking to make career change, but ya'll are scaring me

Hi all - I've been perusing this sub today, and would love to throw my situation out to you and get any input/feedback/resources you might recommend. I'm 35 and have been working in ad agencies for the past ~13 years. I've been successful and worked my way up the ranks and am currently in a director role, but vet school has been something I've thought about for years - I'm a vegan and passionate animal advocate. Given my Advertising degree, I have A LOT of pre-reqs to knock out + GREs before even applying to vet school, but I truly think I could do it, because I'm so passionate about animals. I volunteer at the local city Animal Control, so I know the not-so-glamorous side of an animal career. And I'm mentally okay with leaving a high paying job and taking on A LOT of school debt - if this means being in debt for the rest of my life, it feels worth it. Advertising is no longer my passion, whereas animals always have been. But am I being foolish? Are there resources you would recommend that I tap into before taking the leap? THANK YOU. I've always been so grateful for the amazing vet care my pets have gotten, so I appreciate all you do.