You are who you are. If you are not ready for the big "L" word. Then let him know. If it happens it happens. If he gets pissed then he isn't paying attention or wanting to understand your feelings. If he is understanding then he will also not have a problem waiting for it. But none the less don't lie to him. Lie once and it will be in the back of his mind for a long time during your relationship.
Experience is never gained until just after you needed it.
Luck - That is where opprotunity meets preperation.