How can I know if my sourdough smell right?

Hi everybody and greetings for the amazing forums

I started my interest in bread baking several months ago. Read a lot in Peter Reinhart's books and was excited of sourdough breads. Due to several bad experiences I abandoned the idea for a while, and now back to it.

Actually made a whole wheat starter according to Reinhart instructions (including the pineapple juice) - and that starter came into life very quickly which was so exciting. The problems started when creating the mother starter. I don't know if I left it outside too long, but I suspected that it didn't smell so good (although written in several places that that is normal). Made my first 100% whole wheat bread according to his master formula. That "bread" ended in the garbage :(   it was so sour not to say rotten, and completely fall apart - ????

I had a back-up of the starter in the fridge (the one before making the mother starter) - which came back to life very quickly with white flour.

I fed him, and after 2 feedings - again the feeling that the smell is not so good

How can I tell if my starter is rotten or contain the undesirable bacteria?

And how do I make it to the starter needed to sourdough breads (I mean the ratio of starter:water:flour)? are the quantities in oz are usually given as a volume or weight?

I want to try and make Jeffrey Hamelman's sourdough seed bread and did not know how to make my starter into the levain described by LindyD: Liquid levain:
4.8 oz. bread flour
6 oz. water
1 oz. mature culture

- wheight or volume? can I start with my starter?

Thanks so much for your help!