I agree with the above post. Because you had a panic attack in there, going back in there stresses you out. I'm the same; my DP developed after a couple bad weed trips and now every time I smell weed being smoked (even just on the street where I know there is no way I'm inhaling it), I start to freak out a bit. The important thing to remember is that your room is just the same as any other place, but the thing that feeds panic attacks is the fear of having another panic attack, and since u had a panic attack in your room, understandably u feel panicked or stressed in there. The quicker you realise and accept the reason why u feel like this in your room, the quicker u can start relaxing and enjoying life again
hope this helps.