Often, (not every time) a few hours after I kiss my gf I get fever like symptoms such as muscle soreness and fatigue. These symptoms last for a night and dissapear in the morning and never show up again unless we kiss again. my gf doesn't have any symptoms and is in good health, this does not seem like MONO because MONO only happens once in life time and the symptoms last for few weeks not just one night.
Maybe you are allergic to her lip balm? Make her wash those lips before you try kissing her again and see what happens.
The more likely reason is that all of your blood is being concentrated in one area…if you know what I mean…Your blood is gathering at the wrong head and it is causing you to feel light headed.
I think your girlfriend may be an amoeba.
your girlfriend sold her soul to the devil