I don't know which office you are using @Brenda5 but that is absolute rubbish. I've just put in my third certificate, I didn't even have to wait to see someone, the door bitch, who is a snarky cow, just took it and submitted it for me.
I am working a couple of days a week and the certificates reflect I am OK for light duties. My GP, bless her, has said I'm not fit for onsite work but that I can work from home so I can rest when I need to.
I haven't heard one peep from them. Maybe because I am working I'm not technically unemployed so I dont screw up their stats.
I wish I could come in and help you. Go to another office if you can and make an appointment to see someone who knows their stuff. It will be worth travelling to get away from your current location which is apparently populated by incompetent idiots.
This shit should not happen. Margxxx