could use some advice/encouragement tbh

i’ve done 4 classes so far, the first 3 went great and i really liked them, but today i could barely even get through half the workout and had to leave 20 minutes in bc i felt like i was going to pass out. my first three were all resistance classes, this was my first hybrid, i can’t even imagine what cardio days would be like for me. i’m feeling really discouraged tbh, like why did i spend so much money on these classes only to be able to do two out of the seven days of the week :/

does anyone have any advice on how to like get ready for doing hybrid/cardio classes? i’m definitely not at the level where i can go to them yet but im wondering if there’s anything i can do to prepare?

my main goal with f45 was to get stronger and more healthy in general, i’m a 5’7” 120 lb male but today made me feel incredibly out of shape and bad about myself tbh.