I’m doing my two week pre-op and now I’m having second thoughts…

I’m doing my two week modified liquid diet (two protein shakes + one lean and green meal a day). At this point I can’t tell if it’s working or not — I feel like I’m messing up somewhere. I’m having trouble using the bathroom, and I’m concerned about the next few months in terms of going back to solid foods. I have heard horror stories from people saying that when they tried to go back to solids and weren’t ready it hurt them, has anyone experienced this? Can anyone who’s had it within the past few months explain their experiences?

I feel like I’ve gone too far to back out now. But I want to make sure that I’m fully comfortable with doing this. I don’t know, I guess I just need to speak with others who have had it to let me know that it gets better.