I'm allergic to my bedroom

In 2006 and 2007, I lived with my grandma for about a year. After half a year (can't remember if it was 2006 or 2007), my right eye started stinging. Or itching. I had been working in the garden that day so I though there was something in my eye. Later that day I went to the eye doctor but she couldn't find a thing and prescribed me some eye drops.

The itchy feeling was at it worst when I was in my bedroom. A description of my bedroom:

• Garden view.
• Single glazed windows.
• Floor: old carpet.
• Old wooden closet with a miniature earth globe on it.
• Brand new wooden desk with metal legs that have some rubber on the bottom.
• Desktop computer, computer screen, laptop, laser printer, ...
• Wooden bed, duvet, bed sheets, ...
• House was situated in the city.
• Not much traffic passing by.

After my mom settled in her new house, I occasionally visited her. The longer I stayed with her, the better my eye got. So there had to be something in my bedroom at my grandma's that would cause the itchiness.

Update
8 years later, in 2015, I visited my grandma and took that plastic globe standing on the closet home. I put it in my living room and after no more than an hour, my right eye started feeling itchy again. That moment, I knew what had been bugging me 8 years ago: It was the plastic globe. Originally that globe stood in her living room. I remember playing with it as a little kid. So maybe she'd put it in my bedroom after me living there for about half a year.