I'd think everyone fears it at least a little bit, especially in the beginning, so I'd say that's totally normal.
I didn't know where I'd end up in the beginning. There is no way I could've imagined or believed anyone if they told me I'd be where I am now back then.
I started off on this journey before I knew anything about transition or about being trans. When I did learn about it I was kinda shocked to be honest but kinda excited too. I was like wow, this is a real thing and like there is a process to fix it.
I spent quite a bit of time after that being where it sounds like you are now, questioning things, looking for the end result and the process of going from here to there, do I really want this, can I really do this?
I took things really really slowly and safely at first. I started with therapy and support groups, learning and talking bout this and my thoughts and feelings and fears. Started laser shortly after, figured always hated my facial hair, why not get rid of it once and for all, if I decide later I don't wanna go thru with transition can stop there and still have something that I wanted and wouldn't regret; a clean face w/o shaving. Started going to therapy and group dressed after (switched clothes in my car..). Had already experimented with herbs for feminization prior to all this (hair was getting shaggy too by now pre trans awareness), wanted safer, real deal meds, so started hrt. I STILL wasn't sure I could do this, go thru with it but I had to try. Few months after that I started going more doctor appointments in fem; I figured why not, they're gonna know whats up anyways after tell em bout my meds (could've lied but didn't wanna) and figured those places pretty safe. Finally got dragged out in public public one day (mall), world didn't end, nothing bad happened so continued doing so more and more and here I am now, basically full time.
As for the part about the point of no return, I guess it depends on what that means to you exactly. For me, I'd say I have reached that point now for the simple reason that I can't ever imagine or see myself going back to trying to be a dude all or most of the time anymore for any reason. Physically I believe I may be able to do it and pass and all but mentally I just couldn't. Depending on breast growth and surgeries and stuff, you could prolly go back and forth for quite some time, many people do do this, or it could be that your blessed (or cursed) with your genes and couldn't easily after hrt due to quick growth, it just depends.
Hope this helps.