Does the word "just" used here mean the same as "literally"?
No, the word "just" in this context is not quite the same as "literally". "Literally" means in an exact or literal manner. "Just" in this context could mean exactly, however, it is mostly used for emphasis in this context. The word "literally" can also be used for emphasis but it would not sound right to be used in this context, unless you removed the word "really". It would also sound much more informal to use the word "literally" in this case, because when used just for emphasis, it is almost like using slang. Here's a couple of examples: Ex: She literally laid in her bed all day. Ex: He just sat around and watched movies all day.