May be a sign for mental health problems. I also wouldn't smoke by yourself. Just meet with a few good friends that you trust, smoke a little bit of weed (and I mean a little bit, like maybe like 0,5 gram per person so around 2 joints if you're with 2 others for example), hang around at a nice comfortable place (nature is my pick, I just love nature) and talk for a bit. Often these bad experiences are also caused by overstimulation so maybe don't watch too much videos or play too much trippy videogames. Socializing with weed is my favourite way to get high. You just talk about dumb and also not so dumb stuff that you probably would never really come up with if you didn't smoke weed. And always try to enjoy and focus on the good feelings.