To quote flatbusher, take a deep breath. Slow down.
20 is young. Very young. You are still growing up and maturing. It is 100% ok to not be married at 20.
It sounds like you need to ‘get out of your head’ a bit. Very often the we work ourselves up and become anxious from the voices in our head. Breath. Go for a walk. Get some fresh air. Do something that you enjoy. Most importantly don’t let yourself fall into a negative spin.
I have faith that you will find the right person at the right time. With a healthy state of mind I know you’ll be ready to build a bais neman b’yirael.