Hi Michael,
STOP DRIVING DUMP THE ENTIRE CONTENTS OF THE FUEL TANK REFILL WITH DIESEL PURGE THE FUEL LINES REPLACE THE FUEL FILTER and with cross fingure PRAY IT'S OK. If you've done this and still have problems, the petrol has attacked various seals in probably the injector pump and or injectors. Could now get expensive. (Note that in cold countries, a 10% petrol addition is allowed to prevent waxing, so you may have got away with it?).
thankyou,