tranny problems

hey i don't know if this is the right forum but i have problems. i have an accord 94 ex with auto transmission. i noticed one day while i was driving it stalled momentarily but then it was fine. but then like a few minutes later as i was pulling up to my driveway my car didn't want to move, it was running fine but it was as if i put the car in neutral but i didn't it was in drive. I tried every gear and all that happened was a lot of reving like if it was in neutral. so i turned the car off and back on and it worked fine. But now everytime i turn the car on, after a couple of minutes of driving the samething happens. what the hell is the problem. i have h22a that came from japan but its on hold by U.S customs. its been a little over a week. i don't want to spend much money on the existing transmission because im going to swap it out as soon as i get the h22a. please help.