Gears slipping ? I think

Having an issue with my 2019 300S It mostly happens in reverse, when I put the car into reverse m, & try to push down on the pedal, the car with shake/rumble like if it doesn’t want to move, if I do want to reverse, it has to be pressed very very lightly & slowly. Similar thing happens when trying to get out of first gear, once I’m on 2-3-4-5 it’s okay, but just trying to get out of a stop, it struggles, not as bad as reverse, but I don’t think it’ll take long to catch up. When trying to reverse up my driveway, which is inclined….. yeah that’s a no go, it’ll do the rumble & then the car does that thing where it automatically throws you into park & then I have to manually move the shifter from reverse, to park, & back to reverse. Today it happened to the point that it wouldn’t even let me go back into reverse no matter how much I switched gears. I had to turn the car off & back on because I wouldn’t want to reverse anymore, almost like if I would’ve put the car in Neutral where it was just revving. Help pls 🙂 I’m assuming my gears are going out but hoping there might be somewhat of a possibility it’s something else. Anybody experienced this before ?