I have had a few of these types of experiences over the years, but I have never actually seen the hag, but I have seen the shadow man that is also often mentioned in these stories.
The scariest one still creeps me out when I think about it. I was in bed and I had this feeling that a bunch of small creatures were in my room. I didn't open my eyes, just had that feeling. You mentioning the distant laughter is a good way to describe it, maybe that's why I got the impression there were a bunch of tiny creatures. I then felt something on my bed. I had a buddy that used to crash on my floor all the time, and initially thought it was him trying to wake me up. How ever he was not there that night. I still had not opened my eyes, cause now I didn't want to see what was on my bed. I then felt something pushing down on my chest. It felt like I was going to be pushed right though the bed, and if I didn't stop it, I was not going to wake up.
At this point I tried to get up and yell, but I could do neither. The pushing down stopped, but what happened next was even worse. It felt like a giant hand took hold of me. What ever it was picked me up and slammed me against the wall then back on the bed. Then it was over. I could move and talk again. I sat up and when I did I thought it had to have been a dream, but the fucked up thing was when I sat up, I was facing the window. The way my bed was set up, when I sat up, I should have had the window behind me. I had clearly been flipped around. I also had a bit of bruising on my ribs and chest. To this day I am not sure what to make of it all.
Since that happened, I have had other, but lesser experiences. Every time it happens I have been sleeping on my back, which I rarely do. I know now the feeling that comes with these experiences, so if I get that feeling, I make sure to wake myself up fully and change position and then try to go back to sleep. These ones my have simply been sleep paralysis, but I won't risk it.
The last definite experience I had was actually kind of funny. It happened during the day. I got that feeling someone was there so I opened my eyes and seen a shadow man standing at the foot of my bed. Being in the daytime, he was very clear. I was able to move this time time though. I remember being more annoyed then scared. I sat up, looked right at it, and told it to fuck off and then rolled over and went back to sleep. Haven't had an experience since.

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