Boobs

Okay so I usually am really self cauntious about my boobs and I've worn push up bras for years because I thought my boobs were kinda saggy for my age. For the past week or so I've only been wearing those like halter bra things with no padding that you would wear with a tank top or something with no back or something and it seems like my boobs are wayyyy perkier. Is this all in my head or ?