Good day yourself!
Drawing with a mouse can be a challenge, but I've known people who have gotten the hang of it. When it comes to digital mapping, you can also look into other styles than the more traditional hand-drawn look, which can be easier to handle without a tablet.
Now, all that being said, if you want to draw maps by hand then I'd say a graphics tablet might be a worthwhile investment at some point - the cheaper models are not that expensive (although of course that is all relative) and can make your life so much easier.

Anyways, welcome to the Guild! You seem to have a pretty good handle on maps already, so I look forward to seeing where your digital mapping adventures take you.