Gosh, the second image could be anything...

The leaves are drooping downward in the first image, so that limits it down to three possibilities:

-underwatering

-thrips-- tiny pin-head-sized quick-moving bugs under the leaves and in the petals

-white flies-- tiny white flies flying up your nose when you gently shake the plant

-spider mites--Check under the leaves (especially the dead ones) for tiny webbing, or a brown smear in your finger when run on the underside of the leaf

Regardless what it is, keep watering, take all the damaged leaves off and THROW AWAY in your trash, and wash down the plant in soapy water, followed by a horticultural oil. If it isn't little critters (which would surprise me), they will soon make an appearance since the plant is weakened right now. Be sure to lightly fertilize, so the plant can have a boost of energy to make a come-back. Do the same full treatment to the plants next to it, as they are already infected & will be next to collapse, if it is indeed little critters.