Feeling horrible. Anyone else?

I just had to leave work because I feel terrible!! I work in the kitchen at a fast food restaurant and I made it about an hour into my shift before I started to get really weak. Then I got lightheaded and confused, like I just couldn't think straight. I asked my manager to move me to a less strenuous position and that helped for a few minutes but then it came back even worse. I made it another hour and a half before I started to get some low cramps and pressure. Finally, I felt like my legs were going to just give out from underneath me. I told my manager I needed to leave. The drive home felt like hours. I'm in bed now but I'm so tired and weak that I can barely hold my phone up and even talking is too much work. Anyone else going through this?