Crassula perforata - string of buttons question

My string of buttons put out flowers from several stems. I did my best to pollinate them between each of the clusters with a paint brush. I don't know if they successfully pollinated, but the flowers have dried up so I cut them off into an envelope to dry completely.

I've grown succulents from seeds successfully three times before, but never had any give me seeds of their own. I know the seeds i got from sellers were tiny, almost comical in size. Is there a way to know if the flower properly pollinated? How big should i expect them to be? Is there any way to tell seed from dried plant matter or does anyone have pictures showing how big they are?

I know it sounds like a rather newbie question, but I enjoy the feeling of growing things from seeds. It's a fun challenge and good to know if i try to make hybrids down the road. Thanks in advance.