You're not being unreasonable...that's just lame. She shouldn't have offered and then yanked the offer back like that (esp. when she knows you are already upset about your b-day, etc.). The best way to handle the situation once she made the offer was to ask that you get back to her with an answer w/in, let's say, 24-48 hours, and then she could fill your timeslot if you decided not to attend your usual appt. But if she was going to so quickly rescind her offer w/out waiting for an answer from you, she never should have offered at all.