Lola had the same problems, but we just continued on...the car rides became bearable... she used to bark and cry and whine and now, she just sits quietly and looks around her. As for the nailcutting... I tried this with her the other day and it worked pretty great. I've been training Lola with treats and I used those treats (broken into itty bitty pieces) and leave them on the table. Her attention is focused on the treats on the table rather than me, and she's so busy "stealing" bits here and there that she didn't even notice I was finished cutting her nails! I even cut one too close and it started bleeding
It was ok though, she was a trooper. She was so busy eyeing the treats that she didn't even notice the little bit of blood!
Good luck to you!!