Diarrhoea and severe pain for week

[NailsHairNipsHeels]

Last Thursday I started with really bad stomach pains up under my ribs and felt a bit sick. By evening I had a really upset stomach. Thought it was something I'd eaten and avoided food on Saturday.
I've only eaten toast and ready salted crisps since because anything I eat is having the same results. The gurgling from my stomach is ridiculous as well it's really starting to annoy me/worry me a bit.
Can't get a gp appointment for love nor money.
I'd there any tried and tested fixes? Should I be concerned it's gone on this long?
I do have mild IBS but nothing like this previously