Can you smoke 2 month old weed?

I stopped smoking a month prior to my surgery. Today is the day after my surgery. I haven’t been able to sleep comfortably because I’m so afraid of hurting the area with the stitches. Also because i sleep with my younger brother (who’s at school now) but he sleeps crazy so I was afraid he’d hit me. I’m in pain & I took a Tylenol but it’s not working much. I remembered the weed I had left over from when I stopped & I was wondering if it’s gone bad? It wasn’t stored in an air tight container, it was stored in an envelope. Is it still good?