Letting people down

I hate doing it but it seems almost inevitable in life that sooner or later, you'll let somebody down and now I've just done it bigtime and am feeling terrible. My chiropractor asked if I would would cover four reception shifts over the next two weeks. Mondays are six hours, from 1-7pm. Wednesdays are a beastly ten hours, from 9am-7pm, with a break midday. Minimum wage.

Last time I did cover for them, there was no computer and you just wrote down appointments in a book, rubbing out cancellations and rearranging, all in pencil. Now, though, a new computer program has been installed and it is fiendish. It is full of glitches, passwords, one left click followed by two right clicks... a whole six pages of instructions had been scribbled out for me. Then there's doing the credit card payments, totalling everything up in several different ways at the end of the day, two safes with various keys to be hidden, gowns to be washed but not left in the dryer overnight and the wash can't be started till the last client has gone (so how can you go home at 7pm?) and, worst of all, there were three or four different doctors and therapists going to be there, not just one, and you had to handle all their clients and phone calls and appointments.

Each time a client arrives, you have to go onto the computer and click a box that says they have arrived, then another to say they are having their treatment, then another to say they have paid and how much, then you have to prepare an invoice, and also keep different payment sheets for each doctor/chiro... This is just the bare bones. There's far, far more. After an hour and a half, my head was spinning, my spirits were in my boots, I couldn't cope and I wanted to go and lie down.

Anyway, I got home and tearfully emailed the main chiro who owns the business and told her I couldn't do the shifts as I just couldn't cope with all the work involved. There's the fatigue factor, too. I'm not sleeping well again, I get up each morning feeling tired out and keep having to have lie-downs in the afternoon. Perhaps I'm just too old to work! I feel terrible, really terrible, about letting them down and it's significant that I've had no email back, either berating me or saying 'never mind'. I feel as if I really have left them in the lurch. But what else could I do? Put myself through hell and mess up all the appointments?

Maybe I have to face the fact that I have the mind of a writer, not an admin person. I now admire and respect both their part-time receptionists (one of whom is 60-ish, like me) immensely. I had no idea how hard they had to work. There's a lot more to being a receptionist than just sitting by the phone.

Or is this particular job just exceptionally detailed and demanding? I'd be interested to know what you think. One thing's for certain. I'm going to cancel my own appointment for treatment on 4th May because I don't think I can ever show my face there again.