@simonsaywha Why don't you start with the first part, as you'd planned originally and take it from there?
I've done that with my story, which started out as a 25K novella about 'their beginning', but then readers wanted to know what happened next so I've continued the story with a Part 2 'falling in love' which should bring it a little over 50K. The nice thing about Wattpad is it's really flexible and I think 50K is a good length for a completed work...