you're not the worst owner ever! the fact that you care enough about your bunny to show concern over her happiness shows you're the opposite of a bad owner
here's a list i've compiled for you of things that are probably lying around your house right now that you could use to keep your bun entertained:
plastic cups (to toss and roll around)
cane basket (untreated without the sprayed on gloss coating)
cardboard boxes
old phonebooks/magazines (to dig and chew and tear and make a mess with)
baby rattles/keys/toys (not the teething kind though, too easy to chew off the soft plastic and swallow)
pinecones
a towel or blankie (but careful not to let her chew off and swallow loose threads, they can cause tum tum upsets)
a box filled with shredded newspaper
tennis ball
scrunched up ball of paper
drape a towel or blanket over a chair so your bun can pretend it's her tent lol
fill an old drink bottle with rice or corn kernels to make a rabbit rattle (make sure the lid is tight so bunny can't get into it and eat the rice/corn!)
milk bottle/coke bottle lids
tissue or shoe box stuffed with hay
tip up some chairs and make a temporary bunny maze. place some treats in and around the chairs so your bun has to find them!
that's all i can think of for now. i'm sure you will have some of those things handy without having to go out and spend $$$