I think I over fertilized my raised vegetable garden. A few days after I fertilized, the leaves are starting to go limp and point downwards. Is this what it looks like? And if so, is there any recovering from this? How can I help my garden get better?
From all the comments and your responses, this is most likely due to lack of sufficient water. We get occasional heat waves where temperatures are high and the vegetable plants in the raised bed are not able to deal with it. I have experienced similar problems and watering the plants during those hot days seems to revive them back to normal. A better approach is to be proactive and water them longer the day before the heat wave hits.
If it was or is fertilizer burn the leaves would start to get brown spots which can take over the entire leaf, until the leaf withers, then parts of the stem start to die. If the plant is resilient, especially is it's a mature plant, or a big plant, it can come back. Otherwise, your plant will die slowly. This doesn't seem like fertilizer burn, it seems like lack of water/too much heat.
I'm confident that you did not over-fertilize, based on what you gave them and how much you gave them.
I believe you're right about the heat, wind and aridity being key factors here, but I think sun is also a factor. I would recommend putting the plants in partial shade, making sure they have enough soil, and watering them sufficiently (at least once every two days, depending on how fast it dries).
If improving your watering doesn't help, you may have a nutrient imbalance in your soil. Super hot soil is said to have a different profile of available nutrients than cooler soil (e.g. hot soil tends to have less available potassium and magnesium and more available phosphorus). There's probably a different set of microbes in the soil, too. In my climate, potting soil works a lot better indoors. I don't use it outdoors, because it historically has killed most plants (oregano survived, though). However, given the right additions to your soil, it may be workable.
I'm guessing your soil gets quite hot due to the sun both on the soil and on the container. The porosity of most potting soil is high, which may allow it to dry out faster than regular garden soil in an arid climate. Increasing moisture retention and decreasing soil temperature may help. Adding organic matter (e.g. compost) may help with the moisture and nutrients. Mulch might help. Painting the container with something that reflects infrared light may help to keep the soil cooler, although I'm not sure how expensive or easy-to-find that would be (and that would make it cooler when you want it warmer).
Anyway, I'd start with compost (for organic matter), watering sufficiently, and partial shade. The way the leaves are curling and turning upside down is a sign that the plant is trying to lessen the amount of light it gets on those particular leaves. This could indicate something bad about the health of your roots, though. Plants with disturbed or insufficient roots tend to be more sensitive to strong light.
Again, make sure you have enough soil. I recommend at least 5-gallons per plant. I like to use 10-gallon moving totes for my containers (especially for peppers; I can put two peppers in one tote, although I'm testing out how just one plant works, this year).