But given how warm and sunny it's been lately, I'd consider giving it a little shade for a few days until it perks up. A piece of shade cloth or frost cloth, or even a few palm fronds stuck into the ground around the plant will help it out. The flowers on mine are just about done for the year now so you shouldn't expect those on your plant to stay too much longer anyway.
Just because a plant says 'full sun' on the label, doesn't mean a baby plant with a small root system can go directly out into the blazing sun without a transition period. Once it perks up and starts to show some new growth, you could gradually ease it out into the sun, but it's probably spent a good deal of its life (if not all) in a greenhouse, where it would have controlled temperature, no wind, high humidity, plenty of water and probably the shade of nearby plants to keep its roots cool.
Another mistake a lot of people make is planting so called "drought tolerant" plants out into their garden, then assuming they never will need supplemental water again. Any plant newly transplanted needs water every day for the first week or two, depending upon how hot the weather is. Then as it gets its new roots out into the native soil, you can gradually withdraw the supplemental water, but especially in spring and fall when it can be very hot and not rain for weeks, you will always need to keep an eye out for all your plants to have drought stress. I have lots of "drought tolerant" plants in my yard, but no plant ever goes more than a week without a drink, if it doesn't rain.
with everything dyzzypyxxy wrote. Give the plant some shade and some tender loving care for several days. The plant worked hard to produce flowers and now it is a bit shocked and needs to work to produce new roots.
