I feel horrible....i weigh 51 kilos but feel incredibly overweight even though i know i'm not?

I've always weighed 48 in the winter, and 46,45 kilos in the summer time...after I broke up with my boyfriend and started working...i gained up to 51 kilos....i understand i am not overweight...but I can feel my body..when i walk, it feels sooo heavy on my feet! :( i am 5'5...anyone else had the same experience of gaining weight after a break up and having your meal schedule messed up because of work schedule?i always pinch my cheeks because i feel my face is fuller and i have a phobia of my thighs touching together soon...i am so depressed and don't want to leave my house