Dude I just lost a cycle due to spider mites and if theres eggs then there are mites, nevermind the fact that those eggs will be hatching and there will be thousands more. What ever you do dont stop treating your plants, wipe down underneatrh the leaves, I even used a shop vac to suck up webbing, mites, eggs and anything else that was there. They are tough, durable little bastards that dont go easily, Ive beat them before but they kicked my ass this last time and I caught them early when only one plant out of 24 was infected and I ended up losing 18 plants that to the naked eye didnt look all that bad, not good, but it looked half way smokeable, under the microscope there were tons of dead and live mites, just white looking shit everywhere, its a different story on the microscopic level. Thats why alot of good dispensaries will thoroughly test samples from weed they buy to look for bugs or traces of mold/mildew, in order to protect their patients. Youd be surprised when you had some of the best lookng chronic in your hand and went and looked at it under 100x magnification to see all nasty shit chilling there waiting for you to smoke it up...check it out sometime and you "mite" be surprised