AITA for not wanting to buy my gf a bag

so my gf is going to vietnam and shes been working and she earns way more than i do because im just studying and i dont have time to work. i also just bought a couple of things for my school and have also bought myself a pair of airpods that ive wanted for awhile now so im low on money but she really wants the bag. i just dont think its fair that shes going on this trip and is working, earning much more than i am but still wants me to buy the bag for her, but in her defence its only about $70 and i would buy it if i did have a job