Asshole move???

I had to call into work today because I physically can’t walk. I have pulled a muscle in my foot really bad. I am on doctor orders to wrap it, ice it, soak it in warm water, and keep it elevated. All they could do is that and give me pain meds. I need to go do some grocery shopping. My dog needs food and so do the hubby and I. I would have to go around in the wheelchair things. My store I work at is the cheapest in town and I get a discount. Would it be a total asshole move to show up to work after calling in? I’m worried they will ask me for a doctors note because I forgot to get one. They forced me to have one last time when I spent the day in the hospital. I really need to go do this shopping, but I’m worried. Any advice please???