Sensing bad or evil in my dream

I have a reoccuring dream that is scary and bothers me. I sense evil, or something not positive and it's always to the left of me. I don't "see" what this is, it's more like I sense it being there. If I pray for God to keep this evil away from me and my family, I don't usually dream about it. Last night, I woke up from this dream and I saw a guy with something on his waist, like a cannister of some type, sensing it was not good again. I've had this dream off and on for years now. I've had lots of stressful situations at times in my life and wonder if it's tied to that. I just know that's it's scary and sensing that it's not friendly, really bothers me.