i noticed the day after riding my rear shock had a small puddle of fluid under it on the floor of my shed. i'm assuming there's a leak of some sort.... but i'm not sure if there is a fix or if it needs to be replaced?

PS i noticed this before but thought nothing of it, also the rear shock doesn't seem bad the rear doesn't lift up if you pick up the rear. it squats quite a bit when i'm sitting on it though... i weigh 160 but i don't know if this is normal?

any help would be great thnx