What Causes Itchy Vagina Post Masturbation?

i masturbate with my underwear on, and my vagina has really started itching. do u think its cuz of the masturbation? i have had a few yeast infections before, and usually when my husband ejaculates inside me, it leads to a yeast infection, so he generally ejaculates outside. he has been away cuz of which i have been masturbating alot, however i do it with my panties on. do u think its the panties leading to this severe itch?