To get out of bootlooping: Hold Vol+ and Vol- together, then connect USB to a computer and hold both keys until you are back into the download mode. There is a thread on here with a more detailed explanation.
Your problem is most likely due to the fact that the TWRP version you installed does not match the OEM kernel version. (This could be explained better in the OP). Solutions are:
1. Install an old TWRP version which matches your kernel version.
2. Update the kernel source by installing the newest OEM stock version first, then installing newest (and fitting) TWRP and your custom rom afterwards.