Living under guilty conscience

When you do something wrong by accident and you get caught; why do you feel heavy inside? You tried your best to beg for mercy but it didn't work out, and you continue to live under this guilty conscience. Is it because you're fear of the consequence of what you did? are you fear of what the future might look like? At this moment, you feel lonely, you feel like no one cares for you, you feel like you just want to be dead already, yet you don't want to. You really want to get out of this burden, this tough situation, don't you? Interestingly, this feeling only happen for a little while and it's gone, so when will it be gone? Is it the chemical reaction inside your head create this feeling? Or there is a spirit inside of your soul rebuking you? what is that? what is going on?