Auto body repair & detailing: auto body, dual action sander, spray guns

Question
I fixed a dent that I had on my car and i used the spray can primer which cost about two dollars and I was wondering when I paint the car would it affect it and if so what should I do to fix the problem before I paint it.
I have another question I wet sanded the rest of the car with 220 sandpaper so I can paint the whole car and someone told me that 220 was to course and I needed to sand it over again with 600 because if not, when I do get ready to paint it will show all of the scratches is this true and if it is what should I do? Thanks Ernie.  

Answer
I guess my first question is , do you have all of the equipment to do a paint job , spray guns ,dual action sander , air compressor ,etc.Yes 220 is too coarse if you have a D/A sander then you can use 320 grit because the sealer will cover the scratches.If you aren`t planning on using a sealer then 600 wet is about right.As far as the priner the spray can primer is a laquer and is a very cheap product and will not provide long lasting quality,for this you will need a urethane primer if you want good filling qualities and not have any shrinkage later on.