Hi, Ive Always Got Bloated Belly, Everytime I Eat Food

Hi, ive always got bloated belly, everytime I eat food I get super bloated, I'm nauseous every day, I get headaches/ migraines as well.
After I eat a meal it gets to a point where it gets hard to stay awake (feel really tired after I eat) I've lost about 4kgs which is a lot for me as I only weigh 58.5kg at the moment and I'm 175cm tall. I've been tested for celiac disease I'm all good there.
Any thoughts as what I should do next...