Standing.... Pain?

Katherine

My boy has begun pulling himself up into standing position on the sofa and even if you offer him your hands to hold. At first he thought it was amazing and was all smiles and happy about it but now he keeps shouting and kinda crying while standing? Has he just decided its not so fun or is he in pain? He stops as soon as he sits back down. Anyone else ever experienced this? Piccy of my cutie :)