I gave up singing for over 20 yrs and when I returned to it found I could barely be heard. So I had to practise a LOT and 6 years on it's just about peaking. But I'm wondering if you've been over singing and maybe not doing vocal exercises. It's very importand to do regular warm up exercises if one is singing regularly. I think others below have already posted links to lots of free exercise videos now on lin, so take your pick, However if you have been dong the right things, taking a rest may help or consult a throat specialist. Good luck