Premature ejaculator?

I inadvertently discovered a way to TOTALLY PREVENT my ejaculation. There is an over-the-counter "cooling pain relieving cream" that contains 4% lidocaine and 1% menthol. It's probably off-label, so I am not suggesting that anyone try it, just reporting on my personal experience. Application to the head and shaft of the penis very quickly, within just a couple of minutes, resulted in a cooling feeling and desensitization. This effect seems to last for some hours. I did 2 applications 15 minutes or so apart, a few hours before sex. I showered so there wouldn't be residue on my penis, only the effect of what was absorbed. As a result, I wasn't able to cum at all! I mean, my wife had a really good orgasm and usually that triggers my own, but no. I was really trying hard to get off, too, desperate for it. I just could not and eventually apologized to my wife and just said I couldn't. Maybe I need to back off to just a single application.