How risky would it be to have Ketamine 6-7 hours after Oxycodone IR?

I swallowed 15mg of oxycodone (no tolerance) at 4PM on an empty stomach, and I wanted to do ketamine later at night (10PM-11PM). Idk how long oxy lasts for me personally cause this is my first time, but I heard it only lasts about 4 hours, so I'd assume that it would've fully worn off by then. Would a 2 hour buffer period be enough for the oxy to not interact with ketamine?

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I'm also on Lyrica. I've mixed it with dissos before so I feel like it wouldn't be dangerous. It just makes it a lot stronger and longer ;)