I really have no idea about the 'blob' I didn't have any as you discribed but your CM does indeed increase ALOT as your pregnancy progesses (more so with DD2 for me). In regards to the spotting, when I was 19-20 weeks pregnant with DD2 I had two cases of spotting both happened after bowel movements, I was told that it was caused by straining even though I did not feel I strained at all.