No! Though, if it’s in the context of wanting to plan a large complicated celebration with many people, with travel / invitations / complex venue / food arrangements, I might think it’s getting close. Basically if you’re planning something for your birthday that needs 5 months notice, fair enough. Or if you’re approaching your 80th birthday and are hoping you make it that far, perhaps yes. Otherwise no, it’s practically halfway between your last birthday and the next one.