I need to rant...

Anyone else's job making them feel like shit for needing to leave early so you don't puke on customers? My nausea has been really bad lately and I told my daytime manager I needed to leave, havnt been able to hold anything down except water, and she rolled her eyes at me and gave me a speech about how if I left early too many times I could be fired (this is the first time I've left early) and that made me feel terrible. I then cried in the bathroom while puking my breakfast up before I could even leave the store. I'm a cashier and I work at Wal-Mart I can't be leaving every 20 minutes to run to the bathroom... sorry needed to rant it out, feeling pretty upset.