Butternut squash

Hi All,

We finally moved house earlier this year and have a single butternut squash plant. It is in a pot as I knew they spread and didn't want it to take up the whole of the 6x4 raised veg bed. It's trailing nicely across the gravel with one nicely expanding fruit. Two smaller fruit were coming on but have gone brown on the bottom and stopped growing. there appears to be more flowers/fruit coming. Am I watering too little and also feeding too little?

First time I've tried growing them so any thoughts/help gratefully received.