STD tests

So, sex Ed did a number on me when in middle school and I'm super fearful of STDs. I've only been w/ one person my whole life. We broke up and since I've been single and ready to mingle;D So um, before I get active again I've been feeling to urge to get tested. Idk I feel like it would validate my preparedness. So I'd like comments on if that's totally unnecessary and how expensive tests can be. FYI, we were each other's first