Your bad. Spirit is only cheap nominally. They will fuck you up the butt on extras, and rarely get you anywhere on time. The costs, both monetary and opportunity, add up quick. I refuse to fly Spirit. Period. They're the only airline I boycott.
It was a fucking nightmare and I will NEVER fly it again if I can help it. The only situation where I will is if no other airline offers a flight at a proper competing time. I have to fly out to NYC and Vegas at different times during the year under pretty tight constraints as far as what days and what time of day I leave, but outside of that I will happily pay extra. You end up paying either way since they charge you for carry ons (40$ per bag), inconsistently apply their 'personal item' rule (had my personal item changed to a 'carry on' and charged by staff when I've taken the same container on multiple other flights and stashed under seat). As you mentioned, I've run into delays on more than one occasion, and they space their seats closer together in coach than other airlines. I could go on. Definitely my bad though. Ugh.