Oh, poor you, ear infections are horrid.
They should always keep a few appointments free in case of anyone needing urgent attention. Call back and try to get through to them that you are in a LOT of pain and being sick/can't go to work/take kids to toddler group basically is interfering with ability to carry out normal daily activity. Offer to sit there and wait if necessary.
Although I'm afraid it may be a bit late by noon, sorry. Can you get to a walk in centre or pharmacy for some advice/pain relief?
Otherwise, they HAVE to offer appointments within 48 hours so demand a slot for tomorrow, not to be made to call back then.