Penno, being self employed, whatever your trade/profession, there will always be times when the phone doesn't ring. It an get dishearteneing I know but all you can do is put in the effort to market yourself, or organise your business administration or even do practise pieces in the garage or something.
I took up tiling to suppliment the "quiet periods" that I thought my accounting business was going through. Started my marketing, contacting suppliers and the like, when all of a sudden in July, I have continuous phone calls for accounting, lots of new business that had been generated by previous marketing work. Currently over run with the stuff and it is intefering with my tiling.
Be strong, if you are good enough in business (first) then tiling , things will happen.
Grumpy