so tired of getting sick

literally every. single. time. i have more than a just one day off i get really sick. ive been working part time in ogp/omni for four months now and i actually don't know what's going on. it feels like i just spend my days off sleeping even though i dont feel exhausted when i work. i had 3 days off and i work tomorrow. last night i slept 16 hours, the last two 12ish. i get really bad headaches, my nose gets stuffy or leaky, sometimes my throat hurts. and no matter how much i sleep i feel so so tired. but then i work and feel better even though work stresses me out so bad and even just a 6 hour shift gets me like 25k steps cause i mostly do personal shopping, or sometimes dispensing. and my feet do hurt. and the lifting sucks. but i don't feel sick anymore