A theory of exciton condensed phase development is presented taking into account the mutual influence of exciton drops and inhomogeneous of exciton density distribution in vicinity of a drop. For solution of the problem the Fokker-Planck equation is applied. The distribution functions of the both the radius of drops and their concentration are obtained as function of exciton production rate and other parameters of crystal. With increasing the pumping the mean radius of drops increases faster than mean distance between drops. The both values depend significantly on diffusion coefficient. The radius distribution function becomes broader in vicinity of threshold of exciton condescend phase development.