If I were you I'd do some linear progression... 2-3x lifting heavy a week with either back/front squats with possible DL. Also, before this I would spend about 30 minutes or so working technique for Oly lifts.
Without the strength and pretty significant conditioning doing Oly is fairly useless.. especially on Bulgarian cycle programming. Let the linear progression bring up your lift numbers and then transition into PM WOD.
As for shoulder pain... where does it hurt -- pic is preferable -- and during what movements (lifts as well as articulations