Today I have been faced with a bit of a problem - my old Redmi 3S didn't boot at all. I could not go into recovery mode as well. But I could get to fastboot. So here's booted to recovery from command-line.
fastboot devices // to see if the device is at all connected
fastboot flash recovery recovery.img // get recovery.img from twrp site
fastboot boot recovery.img // boot to recovery using the same image
And that's all!
P.S. Never go full crazy and wipe dalvik after flashing a ROM.