What Causes Fluttering Sensation In Head After Sinus Infection?

I feel like I have a 'flutter' in my head and chest a bit like palpatations but when i touch my neck it seems to make my head and chest feel like I am pressing the 'flutter' and it makes it worse. Like when you have a cold and sinuses problem when you bend down I HAD FLU 2 WEEKS AGO)it is a worrying feeling