WELCOME to the forums. You are contemplating an exciting ride. Whether or not you should do it alone depends on you. If you are resourceful, self-confident and really have a burning desire to do so, then there is no reason not to.
You have some experience of being there --Did you feel safe? There are other women, on the forums, planning first time solo trips. Perhaps you have seen some of their posts?
It is a great adventure you want to undertake. My advice is GO FOR IT. The fears we imagine, rarely come true in reality. I hope you'll have a wonderful time and keep us all posted about your whereabouts and what you are doing. Good Luck!