Afraid I may have 2 stop working

I am 31w1d today, an assistant cook. I'm on my feet 8/9 hrs a day and last week I got so much pain i couldn't go Into work for 3days...i feel a little better today Monday so going in, however it's still uncomfortable to walk and that's the bases of my job, I'm afraid I may have to stop working sooner than later which gives me less time on maternity leave and I'm afraid I may lose my job. Any advice for a nervous mom? I do have an appointment with my doctor Thursday but very nervous.