sooooo I had 2 periods last month within a few days apart (super weird & never happened)but did have…

sooooo I had 2 periods last month within a few days apart (super weird & never happened)but did have sex on my ovulation days. if I'm going off my 1st period I missed already but if I go off my 2nd it should come by the 19th atleast. Ladies when should I test??????