At first I thought it was lantana. But this seems to be more of a creeper, and now has seed pods in the form of 5 burrs on the underside. I cannot find anything like it in any of the plant id apps. Hoping you can help!
this is an interesting introduced plant called spiny-bur, Acanthospermum australe. It is sometimes considered to be an invasive species, and it is native to South America, as I remember. It is in the Asteraceae, Aster family, but is a rather unusual member of the family.
Dr. Steven Hill, Botanist, SCNPS