Sudden thigh and hip pain in toddler?

My toddler all of a sudden started crying in pain pointing around his upper thigh/hip at first I thought maybe he fell but that couldn’t be I’m a stay at home mom so I would’ve known if he fell, so I started massaging his thigh but he’s screaming in pain if I touch it and it’s worse if he moves his leg, he’s crying in pain every time he makes a movement so that can’t be due to growing pains right? I’m taking him to the ER right now cause I have no idea what could be wrong with his leg and It’s really scarying me right now seeing him cry in pain