None of the above. What you are seeing now are some winter annuals and not the summer annuals that the product would be expecting. The time to spray herbicide is April 15th, tax day. Mid April give the spring and summer weeds time to germinate and mature somewhat. Actively growing weeds die better than dormant weeds. The next time to use herbicide is September 15th. Do that only if you have some spots that need it.

Your best line of defense against weeds is proper watering. Deep and infrequent is the mantra for watering. Deep means 1 inch all at one time. Frequency depends on the air temperatures. With temps below 70 you should water deeply once a month unless you get rain. With temps between 70 and 80 you should water once every 3 weeks. With temps between 80 and 90 you should water deeply once every 2 weeks. With temps in the 90s you should water once per week. With temps above 100 you can water once every 5 days. Where I live in Texas I can usually go 10 days to 2 weeks in the heat of summer (high 90s). There are other factors like sun/shade, clouds, wind, soil type, grass type, humidity, and others I've forgot. The main one is air temp, so go with that as your primary indicator. Why do this? Because weed seeds need continual moisture to germinate and take root. If you are watering a little bit every day, that is perfect conditions for germinating weed seeds. Of course Mother Nature often gets in the way of deep and infrequent watering plans, so you'll have to adjust. If you get a week of rain in May, you're going to have a week problem in the summer. Crabgrass loves a week of rain in May.