99 cavalier won't move in D or 2nd but will in 1st gear to 20mph then D is fine

What is your question?

My gf took off in drive then accidentally went into R and instead of stopping. Heard a grinding noise or so but at this moment she suddenly went back into Drive and then the car would not move at all

What makes this problem better or worse?

Starting out in 1st gear untill 20mph then going into Drive

How long has your 1999 Chevrolet Cavalier had this problem?

6weeks