Yes. I had nobody to take them with, so alone was my only option.
> weren't you scared of having a bad trip?
Not really. I was aware it was a possibility, but I figured worst case scenario was death. Not exactly a healthy attitude, but my mindset at the time was "if this kills me, at least I will have died trying to get better, instead of suicide".
> how long did the feeling last?
The primary effects, I can't say for sure. I didn't have a phone or watch with me. But it was several hours at least. Took them early afternoon, and the sun was beginning to set when I felt like they had worn off.
The secondary effects lasted at least a year, when I decided to do them again the following summer. I've been doing them once every summer for three years, and I've been able to put my life together. I can't say for sure if it's necessary, but I'd rather not risk going back to the way I was. I've managed to put my life back together. It hasn't been easy, but my career is back on track, I have a great circle of friends, and I've even been able to have some healthy romantic relationships.