Well, you haven't specialized very much in your stats, so as a consequence you don't have any really impressive skills. Using a sledge with 8 Strength isn't great, and using knives with 11 Dex isn't great, either. Still, if you really want to, you can get through Normal with this build. You should probably get a whole lot of bear traps and grenades, though, because your main combat options aren't very strong, so you'd benefit greatly from picking up the Grenadier feat and using a lot of thrown explosives.
Just in general, if you would normally dump a stat to 4, you may as well dump it to 3 - you won't succeed at anything with 4 in a skill that you wouldn't succeed with 3, and that frees up a stat point for you to specialize your build more. Also, if you're going to pick up psi abilities, you should try to find 25 points to put into Psychokinesis so you can get Force Field - it's a really helpful ability, and can save your life a lot. You might also want to drop some more points into Mechanics so you can make good weapons for yourself; good crafted weapons will be better than almost anything you can find - even Quake. Finally, if you build your character for the first 15ish levels for one thing then switch to another, you can pretty much count on having a hard time.
If you're willing to restart, it'll make your whole UnderRail experience better if you make a more focused character. If you're finding the game less fun because of the difficulty, I've got to tell you, 19 levels in it's hard to pull things around. It can be done, but a restart would be better. That's just not a very good character build that you've ended up with.
