SD, your WJ has spider mites..Don't panic, they're fairly easy to rid..
Mites work quick so you have to be one step ahead of them..
Take your plant to sink and hose off, thoroughly..
Do you mist? You need to purchase a mister..add 2-4 drops of dish soap, citrus peel, garlic is optional but works..Mix ingredients in mister and spray daily for 2 wks, or until all signs of webbing is gone..This is an organic insecticide I've been using for yrs..I even spray w/this concoction as a preventative.
There are chemcial insecticides on the market, but I don't use so cannot say which brands work best..and most have to be sprayed outside of home..if you have pets most chemicals can harm them.
You can check for mites by setting a white sheet of paper under webbs, tap leaves..you'll see little critters on sheet of paper..
Mites eat juices from plants..leaves usually turn a pale yellow, but it may work different w/WJ because of its purple color..
Even though WJ needs moist soil, do not keep sopping wet..this will attract bugs. Misting plants on a daily basis helps keep bugs at bay, and humidifers in winter work fantastic..Toni