I had a very old lawn. Last Fall, aerated and double seeded and it looked like Better Homes and Gardens.
In spring I used the Scotts Step I fertilizer with halts. Now I used Step 2, Weed and Feed, and the lawn looks terrible. It gets browner every day, I think it killed all the new grass. What shall I do now?

How much weed & feed did you put on the lawn? Sound like you used too much. Your lawn will come back. My neighbor next door did the same thing only he used the whole bag on a very small mobile home lot and burned all the grass but it came back w/no weeds at all. A person I worked with was very lawn crazy and told me to use weed and feed on Memorial Day weekend, 4th of July and Labor Day. Have followed that rule of thumb and my lawn looks great.

We had the same problem with brown patches. In our case, it was caused by overwatering of the lawn. This provides a fertile environment for black beetles who literally eat your lawn away. You might consider applying some Lawn Grub Killer to the affected areas. Ask your local nursery for a suitable product.

If that doesn't work, it may be a fungus attacking your lawn. This stops the roots of the grass from receiving water. You may be able to fix the problem by applying a household detergent in the ratio of one teaspoon of detergent to four and one half litres (one gallon) of water. Soak the affected area with the mixture and then hose it off.

CAUTION
This method can be used ONLY ONCE. Repeat applications will kill grass roots.

Hope this helps.

Can you put grass seed down and wed and feed at the same time.

No - the chemicals in the weed and feed will stop the grass seed from germinating. Usually, the instructions on the bag will tell you when its safe to re-seed.