Its called peristalsis action. This is the involuntary movement of muscles that “squeezes” food down and out of you. It is triggered by you ingesting food so that whatever is in your system already is prompted to exit, so as to make room for the recently ingested food. Since you have been fasting for two days your system went into “hibernation”. You eating “woke” it up big time. This is a pretty normal reaction and it will become less severe once your body gets used to you fasting.

As an aside I wouldn’t have sultanas, or any dried fruit for that matter. Fruit is fine but make sure its whole fruit. Eating dried fruits, you might as well just sprinkle sugar onto your weetbix. Go for your berry type fruits as they contain less sugar.