Help identifying this tiny plant

[nightpaws]

This lil trimming hitchiked in. The picture is out of focus . I was hoping it would multiply but the plant has since disappeared.
It had round leaves and it grew quickly.

 

[WhistlingBadger]

I can't tell without a clearer picture.

 

[CassCats]

Resembles pearlweed perhaps...

 

[Stan510]

Pearlweed is my guess also.

 

[nightpaws]

Thanks for the replies all, I was thinking pearl weed too. At this scale they all look similar.