Clomid Question!

Has anyone ever successfully ovulated on Clomid & then next cycle you didn’t? I successfully ovulated last cycle on 100MG W/ progesterone at 9.09. My cycle started late on 1/17 after taking provera for 3 days and I stopped when I began to bleed. My period lasted the normal 7 days and I took 100MG of clomid from 1/21- 1/25 this cycle and I started LH testing as of 1/28 and so far its all been low w/ the clearblue advanced digital ovulation test & test strips. I have been very stressed this cycle. Im nervous that I back to square 1 and not ovulating again. This is my 3rd cycle of Clomid. 1st failed on 50MG, 2nd successful on 100MG & 3rd still pending.