I suppose your in your position it would be easy to smother you son, but you are the only one that will know that. And all children go through a clingy phase. They call it separation anxiety. Some early on and for a short period. Others will go through it later for longer periods.
AS long as you act like a parent and make sure your son understands boundaries, rules, and there is such a word as no..I wouldn't worry about loving him too much.
But I will tell you that I don't believe a parent really, really loves a child unless they set boundaries, limits, and provide discipline. Being a parent means raising a child to be a well rounded, stable, hardworking, confident, adult. Being a parent means more than just loving your child. If you think about your relationship with your son and you feel you are preparing your son in the best way you know how....then I think you are fine.