It's completely normal to feel that way! Jealousy is a natural, human emotion that everybody feels in some way from time to time. What matters is how that jealousy then impacts your actions/how you deal with that jealousy. If these jealous feelings are making you act negatively towards people then it may be a problem and you might want to start thinking of ways to stop that negative behaviour or minimise your jealousy. Otherwise, I don't see it as too much of a problem. Your feelings are valid and normal - just remember not to let them get the better of you.