Guilt of calling in sick

So I'm 10w tomorrow and I have called in sick at least once almost every week since about week 7. I have been out of paid sick leave, so there's no benefit to "playing hookie." I work at a school as a reading teacher's assistant and tend to work with the kids in small groups and help them to read. I feel awful calling in all the time, I feel like I'm just making excuses to my boss when I'm not and just feel the worst. Either I'm vomiting all day or I'm so dizzy I feel drunk and dont trust myself driving to work. I know if I forced myself to go in that I couldn't perform adequately and would be often leaving to throw up or to lay back for a moment of reprieve. The job is super easy and I love it, but I feel horrible for taking the time off that I need to. I can tell my coworkers are getting tired of it and I'm worried they think I'm overexagerrating or something. It's making me incredibly depressed because at this point I feel like I'm damned-if-I-do, damned-if-I-don't. Any advice or judgement? Should I just force myself to work and put on a face for the kids (which they can always see through, by the way) or am I doing the right thing?