You shouldn't feel embarrassed about it! I'm sure the professor will listen to your idea, perhaps make a few suggestions if she thinks something needs to be changed. Professors have dealt with a lot of students and you shouldn't feel intimidated.
The task itself may be stressful at first but once you get into it, hopefully it will be an enjoyable experience! You just gotta make the most of it. If you think it's going to suck and be stressful, then it will. Just make sure you get a topic that you're truly interested in.
Good luck!!