Car suddenly stopped accelerating while driving

Hello friends.

So I’m completely frustrated, and just dumbfounded on what is going on with my car and was hoping to hopefully get some clarity, and maybe some advice.

Bare with me I don’t know much about cars, hence why I am here haha.

I purchased this car not knowing it is notorious for transmission problems. Almost immediately weird things were going on with the car, and fast forward probably less than 6 months and my transmission was completely shot. I was put in another predicament where I needed to make a quick decision and I ultimately decided to go ahead and drop 3 grand on a new transmission hoping this would end all my car woes.

Well I’m driving my car down the interstate, probably going a steady 70 mph and everything is working perfectly fine. No weird noises, car is accelerating perfectly, car is driving smooth, and all of a sudden my car starts shaking, and it almost felt like I was going over something bumpy but nothing was in the road, and it makes a noise then my car just flat out stops accelerating and begins to slow down. Fortunately I was able to go off to the side of the interstate and turn on my emergency blinkers. I park the car, and turn it off and step off the brake for a moment and realize my car is rolling back. So I turn the car on again, it starts fine, put it in drive, and press on gas. Engine is revving, but no movement, put it it reverse same thing no movement but engine is reviving. And like I said when it was in park it was rolling, so I turn off car, put on e brake and call a tow truck.

Unfortunately I won’t find out what is wrong with it until later this upcoming week, and I have a gut feeling it’s the transmission again. It’s been over a year so I have no warranty on it, called Nissan and they said that I have barely put any miles on it since the new transmission but since it’s out of warranty there is nothing they can do.

I know I will find out answers later this week but I wanted to know if anyone has any ideas as to what happened because I am completely dumbfounded. My car has not been showing any indicators that anything was going bad. The last time my transmission went out there was all sorts of warning signs. There is no check engine light, the car hasn’t been making any odd noises, it’s been driving good up until this incident I’m just baffled. :-(

Does anyone think there Is any possible chance it could be something not major, or do you think the transmission is done with?

Thanks so much in advance!