Wish There Was a Manual

I wish there was a manual for life, somewhere I could look up all the answers to life's questions. I am dating a great guy, buy my mind is full of questions. I'm not sure where the questions are coming from. Things seemed to be going great for a while and then I woke up one day and was struck by confusion. Something is nagging me and I can't put a finger on what it is. Am I so afraid to make another mistake I am sabotaging my own love life or is my gut telling me something? Time will tell, I just hope I don't screw anything up for myself.