Those are undeveloped pods of C.chinense from poor growing conditions. You might be getting bad pollen or flowers developing with wonky ovules. Often times the seeds will be thin with no embryo.
Every spring my local hydro store puts out their chinense plants and the lower canopy is littered with ripe pods that are the size of a pea. The upper canopy produces normal sized fruits as the season goes along.
Here is a pretty comical example of what you are experiencing.