I’m having multiple problems after having my neck fusion of 5, 6, 7?

Im having multiple symptoms after having my neck fusion of 5 6 7 .these. Are my symptoms im having a lot of pressure. In my neck and lower back it cause alot of discomfort. My neck and back feel like it is being squeezed which causes a throbbing in my neck and back which causes my heart to race and heat to my neck and back. My legs give out as it takes my breath away. What do you think the problem might be