If you're intelligent, anyone trying to employ you will be able to tell, they don't need to see that you wasted your time getting an A+ cert before you were even eligible to be hired. Nevermind the fact that your cert would expire before you can even get a job.
And even then, nowadays most IT jobs want you to at least graduate college, so getting an A+ cert and being fresh out of high school doesn't even matter because the only job you're likely to get with just an A+ cert is a GeekSquad job at Best Buy.
And another thing, the IT field is FIERCELY competitive. When you're out there hunting for a job, there are going to be people out there that have graduated in college, and have multiple certificates under their belt.
TLDR, wait...