Buy a double edge/safety razor. Get a few different types of blades, find the one that works best on your skin along with a good soap that does the same. The key to all of this is an alum block:
This right here shows you exactly where you're lacking because the places where it hurts your face are where you're messing up your technique and that leads to bumps/irritation.
It might take a bit of time to find the right combo for your skin but when you do there is nothing like it as you look super crisp, face is glowing and its much cheaper that multiblade carts plus you don't get any of this:
Bumps occur due to those multiblades as each pass = 4 or 5 blades scraping against your face and they've got no precision/weight behind them and the tinned gels don't have the same kind of glide as a soap you lather yourself. I wouldn't use one of them setups now if you paid me.
Learn the layout of your face, which way the hair grows where (Alum block, remember?), go with the grain using quality blades/soap and you're good. Anything less is an insult to yourself. If you're bumped up now, grow your struggle beard to let it all heal first and once the skin is cool then do what I said in this thread and you'll see how easy it all is with the right tools.