What you describe sounds more like an allergic reaction to something you ate or drank, more than the "MS hug".
The "MS hug" is a sensation which occurs in any muscle group that wraps around -- usually it occurs with the muscles that wrap around your torso, but it can occur with muscle groups that wrap around a limb, or even your head and scalp.
Think of it like this: Your overweight but very loving Aunt Bertha, whom you haven't seen for years, comes to visit. And she is SO pleased to see her dear little niece, she runs up to you and wraps her chubby arms around you and squeezes you a bit...or maybe a lot..too hard. The Hug.
The sensation is a squeezing in, almost equally distributed, all around your chest. You're CERTAIN your heart and lungs are being compressed -- they're not. You're CERTAIN your diaphram is being stifled -- it isn't. You're SURE your internal organs are being squashed -- they're not.
In fact, there is no internal damage at all. Your ribs and back bone and all that are protecting everything inside. It's just a sensation, a feeling, of compression.
Folks have run to the emergency room, convinced they're having a heart attack, or cant' breath, or something similar. Generally if you just recognize that it is indeed the hug, and just let it happen, you'll breathe just fine, and over time, it will dissipate. Sometimes that'll happen fairly quickly, within minutes or an hour or so; other times the sensation will linger longer.
I always experience "the hug" around my torso. And sometimes around my head and scalp, a really weird sensation, as it feels like some giant is "kneading" my head, like you'd knead a mound of dough.