When you start to confuse character names in the wrong drama! 

When I know almost everyone in the cast

When other persons/events are referenced/mentioned in the drama

When my eyes feel hurt and dry so much but I still want to watch 1 more episode.

When I am in a drama slump.

When I complain that I don't have any dramas to watch despite having huge PTW/CW/On Hold List.

I know I've watched too many dramas when,

1) Switching countries does not help

2) You go in a circle and end up staring at the same series contemplating weather to watch it or not.

3) both (1) and (2) + you're bored with even rewatching cuz you remember every detail of the drama

When you spend too much time on the feeds and MDL instead of watching dramas.

When you start watching a new drama as soon as you finish one

You recognize at least 3 people from the MDL birthday list at at least 4 days in a week

When  whatching drama is more important than sleeping

When I start to remember supportive character's names

When Netflix doesn't have nothing new to watch

When I start to  think to drama at work

When I start to watch drama's during my working time (work at home)