I have had this feeling for many yrs now, that god wants me to do something in particular, but I don't know what it might be. I pray and sometimes get answers about -- well, just this and that, but it seems the answer is never sufficient or..? so I am kind of confused a lot. Or I was. Nowadays, I just kind of don't bother thinking about such things much--until today..
I think I understand that you are saying... Please don't take offense by the other comments here...
God creates every person with a particular mission in mind for them to fulfill while in this world. God places this desire of doing something in particular in our hearts when He was us to search for answers as to what His will is for us in this life.
Ever since I was a little girl I sort of felt as you do, and I prayed almost every day to know the will of God. It took years before I began to understand the part that I was to play. Yet, the answer was given only after much time spent in prayer. So, definitely pray, and if your heart is open to God's will, He will certainly show you what He wants of you. :)
The Bible says, "This is the will of God: your salvation." (1 Thessalonians 4:3) Focus on perfecting yourself so that when the time comes for you to accomplish the mission which God has ordained for you, you will be prepared to carry it out properly.
Hope this helps!