I know someone who likes to try to be everything to everyone. If someone has a certain pain, then this person has advice on what to do for it. If someone else is having financial difficulties, then guess what? Free financial advice, from someone who isn't truly qualified to give financial advice. Perhaps you're interested in buying a house, then this person will give you real estate advice. If you hear something strange in your car, amazingly enough this person has advice that you'd expect to get from a mechanic.
I think that sometimes we put too much pressure upon ourselves to be able to "perform" for other people. We think that these people need us to be there for them in the form of advice or help. Sometimes, though, other people bring up their problems with us because they want to talk them out with a sympathetic ear there to listen--not necessarily to hear what we would do to solve the problems. And if we put that much pressure upon ourselves, then we're negatively affecting both parties: ourselves because we're putting a lot of stress on ourselves, and the other person because we're robbing them of an opportunity to reach their own conclusions and find their own solutions.
I often have to hold back on advice because I really like to give it, and because I think that the advice I give is good. But I give it too much, and I've often found myself giving advice based on one article or one book that I've read, not based on broad experience and knowledge. I've found that if instead of giving advice I ask a simple question, such as "What do you mean by that?," I can be there for someone else much more effectively than I can if I'm trying to solve their problems for them.
We can't be everything for everyone. We can't be doctor, lawyer, teacher, mechanic, electrician, systems analyst, and all those other jobs that we really don't know, if we really don't know them. So relax! It feels great when you stop trying to solve everyone else's problems and you become a good listener, someone who is truly able to help others to solve their own problems for themselves.