I Woke Up One Day With Pain On My Foot.

I woke up one day with pain on my foot. I thought it was tendonitis but then after a day my wrist also hurt, I ate Chinese food and had diarrhea three times, the next day I felt nausea and vomited. I went to the doctor that day and she said it was an infection. I haven't pooped all day since yesterday in the morning which is also when I vomited. I now have fever that goes away and come back. I woke up today with pink spots on my skin but they are not itchy. I drink a lot of electrolites but after sleeping so much I am very dizzy and unbalanced. I am slow to walk and it hurts the top of my foot and ankle and knees. What can it be?