My sister's husband's neice is getting married next month, and I've already agreed to do the pre-wedding shoot, but now they want me to do the whole shooting match. They have very little money for a pro. How do I tell them no, without sounding like I'm being a pr*ck by saying I just don't want to? I have 0 experience doing weddings, and don't want to learn on them. I don't handle pressure very well, and don't want them coming back and b*tching later.