Transmission/clutch?

[PrimeS40]

Hello there folks. Fairly recently bought an 05 S40 T5 6 speed. Been lurking through y’alls forums basically since I got it, and it’s been far and away the best, most consistent resource I’ve found. And you seem like real nice people to boot! So I’m officially in. Not entirely sure where to start here, also not knowledgeable car guy, just a DIYer(this is how I learn), so lmk if you need clarification or more info(or correct, not with the terminology either, really).
So, I was driving along and then my engine is no longer turning my axles. It had happened a couple times 2 days prior, but after coasting on to the shoulder, I’d put it back in first and it went just fine. Never any popping/grinding, didn’t kick the gear stick at all. A symptom I believe to be related, and had been progressing noticeably right before all this, was that when I would go uphill, the car was very labored. Like I was losing power, almost felt like something was about to disconnect and the act of driving uphill put more strain on whatever it was. Gear didn’t matter, speed didn’t matter. It will still shift into any gear, but something isn’t engaging. I’m in a pretty small town, and I’ve been talking to anyone I can find for about three weeks now. No straight answers. Any ideas? Appreciate the time either way, thank you.
Jacob