Trying To Find My Life Purpose At Age 36

I have been thinking all day about what my life purpose is. It is constantly on my mind. I feel as though the clock is ticking for me for some reason. I guess, I am just afraid that if I don't find my purpose soon, I never will. I feel like there is something missing in my life, and I do not know what to do about it. I am searching for contentment. I feel like I could be doing so much more.
I am a wife and a mother, but I love helping people. People are my absolute passion. I just don't know exactly how I could go about finding out what it is I would like to help people with? I am sorry this sounds so confusing, but is really is. I want to make a difference in someones life so badly. I want to change the way they think and feel. I love to make people happy and see them smile. If you have any suggestions feel free to leave me a comment. I hope you all have a great week. Thank you for reading my ramblings.