Acting odd..

So I’ve tried to feed Fírnen two nights in a row and he’s refused both times, but he did it strangely.

Sometimes if I made a sudden movement with the f/t mouse, he would strike weakly at it. Not so fast that he actually hit it, kind of like he didn’t really care??

Anyone know what could be going on?

Sounds to me like he didn't want to eat and just tried to "scare" the rodent away...

Sounds like a defensive strike, which can be caused my many different things - not hungry, in shed, too big of a prey item, not recognizing the prey item as prey, being spooked by something, something off about his husbandry, etc.

I would double check and make sure nothing's changed recently in his enclosure (assuming you've had him for awhile and he's eaten regularly for you before) and then just try feeding him again on the next scheduled feeding day. There's no reason to keep trying to feed him every day when he refuses - it can actually make things worse.

I second all of the above. I would wait until your next scheduled feeding day and try again. Double check husbandry in the meantime. Could just be a BP being a BP too.