One of the features of a plant that makes it a weed is the ability to bounce back from adversity faster than competing species. The same goes with garden insect pests. Aphids are born pregnant and will drop eggs about a week after birth. Lady bugs take months to go through a cycle like that. So if you spray an insecticide that kills both the aphids and the ladybugs, you will get the aphids back quickly. You will not get the ladybugs back until the population of ladybug food (aphids) is sufficient to support their return.

You can plant before 4 weeks. Sprout percentages will be reduced, and survival levels lower, but you'll get some. It's hard to predict where and how the seed will be killed, so seeding at higher rates isn't recommended. In some areas, if the herbicide went down heavier than average, you might have a complete failure.

Okay I'm in San Antonio and moving to Bandera. Hold off on the fertilizer unless you want to use an organic like alfalfa pellets or corn meal. If you've never seen those flowers then you don't have buffalo. Can you take a picture on a cloudy day from a height of about 3 inches. If the grass has flowers or tassels or anything on it, that would help. You have not used the really hard stuff, but then you did use 7x too much, so I'd let things rest for a couple weeks. Today's herbicides often don't show progress for at least a week. If you have St Augustine, for example, 2,4-D will kill it. Applying anything at 7x the rate would probably wipe out St Aug. St Aug is a very hardy grass, but one weakness is sensitivity to most herbicides. It's weird. Let's figure out what grass you have before going crazy with treating it. If you water the fertilizer in immediately after applying, it should not hurt a normal grass. The problem comes if you don't water it and then the morning dew creates a very salty solution that will kill most grass (but not usually St Augustine - weird). If you have a hand sprayer of Weed b Gon, you could spray those dandelion looking weeds. Just spray the leaves - don't drench the soil. They might be thistle, which looks very similar before it flowers. As for fertilizing the lawn, I'd just enjoy the bluebonnets for a couple more weeks.

"If they used a high rate you will not be able to replant anything but grass for about 9mo-a year." This is a bit on the pessimistic side :-) The active ingredients in Weed-B-Gon degrade quite rapidly in the soil......anywhere from a few days to a few weeks. To be on the safe side you could wait a month before planting but there is NO need to wait longer than that. As stated above, the herbicide must come into contact with plant foliage to be effective - it has minimal residual effectiveness if applied to the soil.