You are correct. It is your responsibility to fix any needed repairs or paint touch ups. As a retired realtor, unfortunately you made a HUGE mistake. You were SUPPOSED TO have your own realtor come with you on your very first visit. The issues are as follows:
Builders use their own contracts written by attorneys to benefit them - not you. Builders do NOT use the standard state contracts that realtors use. Therefore, the contract you signed states something like "Builder will not be responsible for any delays, repairs, unforseen changes or substitutions." Read your contract carefully. I'm sure there is wording similar to what I wrote.
The sales agent at the site works for and represents the builder. Their job is to get you to sign a contract WITHOUT any outside representation (no attorney, no outside realtor and no outside lender). I'm guessing you did not use your own lender or attorney. If you used your own attorney, he/she would have changed the wording and terms of the contract to benefit you. If you used your own outside lender, you would have probably got lower interest rates and lower fees than the lender working with the builder.
The only thing the builder is interested in is PROFITS. Builders will price their brand new homes higher than comparable homes in the neighborhood. Builders know that buyers like you LOVE brand new houses and will quickly sign a contract and pay a higher price just to have a brand new built home.
At this point, you will need to pay for any repairs you want done. The builder WILL fix the repairs BUT they want you to pay extra money to fix it. Ask the builder what their fee is and I'm sure as soon as you pay them the money, they will fix the repairs.