Sounds like your plant has either aphids or a scale insect.* The sticky stuff is called honeydew and is the waste from these pests.* Aphids will usually be found on the new tender growth, succulent stems and the underside of leaves.* They come in different colors.
Scale insects don't move around once they latch on.* They too come in different colors and are usually found on the stems and undersides of leaves.
You can use insecticidal soap for the aphids.* Spray out of direct sun every 5 to 7 days until they're gone.* You can even make your own.
For scale you can use horticultural oil.* Be sure to protect the surrounding area.* Use the same way as the soap, soaking the underside of leaves.* There are several types of horticultural oil.* Most are made from petroleum.* Try and find one called Organocide, made from sesame seeds.* There is another that is synthetic that I DO NOT recommend named Oraginicide.
Stressed plants are often more prone to insect pests.* Check to see if your plant needs to be repotted.* If you want to keep it in the same size pot you can top and root prune.* Top pruning will make it easier to control your pest.* Using synthetic fertilizers can also lead to insect pests.* It's like steroids for your plants and can cause a succulent flush of growth that attracts the pests.* I recommend organic fertilizers such as fish emulsion mixed with seaweed.
When weeding, the best way to make sure you are removing a weed and not a valuable plant is to pull on it. If it comes out of the ground easily, it is a valuable plant.