Yeah you can always add more to the week, just go to the diary, then click on 3 dots top right, and then click edit week, if you want to edit a previous week, just open ur diary in that week and do the same process.
Good growing, nice looking plant.
Yes when you go to your profile look at the top right of your screen you should have 3 dots to press in which will change profile info. If you want to add weeks or pics go to your actual diary of the plant your growing then click on the top right which then you can fully customize that specific diary. Hope this helps