Should I tell my girlfriend the truth about my ballpeepee story?

about a year ago i found out about ballpeepees, the mechanism in pottys that fill it with water. I don't know anything about pottys and I thought it was a funny name for a thing. I ended up calling a Home Depot in my town and kept asking them for ballpeepees, shoehorning the word "ballpeepee" into the conversation gratuitously. No people around, no recording the call, just pranking alone for the love of the game. I acknowledge that at the age of 32 that is immature behavior but I thought it was funny and I really wound up the Home Depot employee, it was hilarious.

A little over a month after that call I'm hanging out with friends. One of my friends brought over this girl from work that none of the rest of us knew. Anyway the conversation moves to the topic of pranks we did as kids. Everyone is going around telling theirs, and I ended up telling the story about how I called the Home Depot and said "ballpeepee" a bunch of times. No one really thought it was funny, which I half-expected, but the thing is I framed the story as something I did when I was a kid. But the girl none of us knew was like holy shit that happened like a month ago at this Home Depot I was at. Apparently she had been there to buy something and one of the employees she approached for assistance had just got off the phone and was chuckling to himself. She asked what was funny and he was hesitant to admit but after some cajoling said that a guy called and kept asking to replace his ballpeepee. The employee said that he would pause before and after saying "ballpeepee" and really put his mouth right next to the phone and over pronounce the word, all the shit I was doing and it was very clear that it was my call being described. I said, like, oh that's crazy I thought I was original when I was a kid but I guess kids nowadays are still doing the same jokes me and my friends were doing as kids. Everyone to my surprise believed me and didn't once suspect that it was me who made the call my friend's coworker heard about.

Anyways cut to now and me and that girl have been dating for about eight months. Prior to the last few weeks, I had not once even thought about the ballpeepee story. Her and I are very close and everything's been going fine until earlier this week. She needed to look something up, and my laptop was open right next to her. I guess the thing she was looking up started with the letter b because as she was typing it my prior searches popped up, first among them being "ballpeepee where sold," a search I had made a year ago to find out where to call with my prank. She asked me about it and I didn't know what to say. So now she's suspicious of me but I can't tell if she suspects that I made that call? Is this gonna give her the ick? Should I just admit I made that prank call when I was 32 and not 15? What do I do here??