You might do a bit of research to see what the range is in your neighborhood. In looking at wedding pricing in the UK on Google I found a handful at £695, but many started at around £1300 and went as high as £2600 to £3000. I judge you to be well under-valuing your services and your own worth.
Consider what your most recent bride wanted: 18 hours of your time shooting the events, plus travel time and time for equipment preparation.
To edit 18 hours of raw footage to a highlight reel and a main reel will take you another 35 to 40 hours, and you’ll need to add in some hours for client review and changes. Perhaps others in the UK can comment on this: in the US I would expect to see a charge of $2500 to $3000 for this two day wedding.
I can say this with certainty: you will never build your company by low-balling prices and hoping to increase them a some later date. Cheap clients are just that. They will never pay more. Many years ago there was a notorious bank robber in the US named Willie Sutton. After he was captured he was asked why he robbed banks. “Because that’s where the money is,” he replied. Successful professionals are like Willie Sutton: they go where the money is.