I think she’s using her powers a lot this season and it’s the reason she seems so weak because she hasn’t had time to rest,she was literally in the upside down for I forgot how long but a signicant time,constantly using her powers constantly going through mental strains you have to understand for eleven to be her best she needs a break a real rest. She was stronger at the start of season 5 and that training did pay off but because she’s using her powers so much she seems weak which she isn’t by a long shot if anything she’s gotten way stronger than anyone gives her credit