I have camped out alone in the UK quite a few times. Basically, there's nothing here that's going to cause a problem. The only difference between settling down in the daytime and the darkness of night is that it is dark (but even "dark" isn't that dark).
The first time for me was in 1978, just after my dad passed away. I just felt like getting away from it all for a while, and so I loaded up the car and set off for Scotland for a month. I stayed the first few nights on camp sites, but then travelling somewhere way north of Ullapool I found a lovely area of closely cropped grass right beside a little road. A tiny burbling stream beside it, which ran into a lake about 100 yards accross. There wasn't a tree in sight! I had just bought a few supplies in Ullapool, and so I decided just to set up the tent and stay a while.
That was my first night out totally alone in the middle of nowhere. I stayed there in that spot for three nights. In my car was a trout fly rod and line, and the little lake (10 paces away) supplied me with enough little native brown trout for breakfast, lunch and dinner each day. The little stream supplied my water. It didn't even occur to me to be worried about being alone, I suppose because that's what I wanted to be.
Camping out alone in the wilds after that presented no problem. I have now done it many times, including all around Europe from North of the Arctic circle in Norway in winter, down into the Italian Alps in summer. I have yet to try it in Africa (Kenya), but I might well do that in the new year, and for the first time I will probably get off the ground in a hammock & mosquito net under a tarp, if for no other reason than getting up high and off the ground away from snakes. (I hate snakes!!)
Rod