Hey there! Hedgehogs are solitary animals by nature; it shouldn’t be recommended that they need a friend. With that being said, some people have housed two females that grew up in the same litter together and had no problems. A lot of times, however, they do start to pick on each other and have been known to fight.
I would say since you’re such a new hedgehog owner, stuck with one. It will be financially easier for you, but you’ll also be able to more fully understand their needs and care. If you do decide to get another girl, and she didn’t come from the same litter or even breeder as your girl now, I wouldn’t recommend trying to house them together.
Hope this helps 🙂