Olympus 35SP Shutter Inconsistency

Hello all. I bought a (so I thought) decent quality 35SP from Kamerastore 6 months ago for an elderly friend of mine. They passed away suddenly before I could give it to them, and it sat in a drawer until last week. I've put about 4 rolls through it.

After shooting a roll today, I was fiddling with the B shutter setting and realized that the shutter wasn't opening at all. After moving the rings around, eventually it started functioning correctly even in automatic mode, but after 10 or 15 presses of the shutter release, the shutter stopped moving again. A bit more fiddling, and now the shutter moves every time (at least I assume, I can hear the timer ticking on the 1sec shutter setting at least.) Is this user error or is there something wrong with my camera? To be clear, even when the shutter doesn't open, the button makes a thunk sound and the shutter seems to twitch.

The aperture ring sticks and needs a decent bit of force to turn when it gets to the A setting, and the shutter speed ring is smooth all around. Both rings are very slightly loose, which I assume is normal.

Edit: Just pulled it out again, the shutter stopped working but after I tried it a few times it finally snapped open a full second AFTER I pressed the release-and then on time every time after. Very strange. I wonder if it has something to do with the meter? Given that it's a full mechanic camera besides, it shouldn't, but it only acts finicky after I put it back in its case. I'm not sure, it's pretty frustrating.