Razor Burn

Whenever I shave I get terrible razor burn along the front of my neck and when I shave I can really feel the razor on the hair even if its brand new and sharp. Right around my throat and an inch or two to either side. I currently use either a 4 blade Gillette or a three blade Bic razor (I'm fairly poor and try to get discount stuff when I can) and Nivea gel. Does anyone know if there is something with my technique or is it the razors themselves? Should I switch to safety razors or would they make the problem worse?