white little flies

i have a plant growing in soil....5 weeks left in flowering stage...doing very well..but....leaves have lots of shiny sticky stuff on them with lots of white specks....and white flies either stuck to the leaves...or if you flick a leave the flies come off....what do you think it is ...should i be worried ...and treatment needed if required thanks

Sounds like white flies, they will suck all the chlorophyll out of your leaves and reduce the plants energy that it can put to the buds.

Yup Whiteflies.....

https://www.rollitup.org/view.php?pg=faq&cmd=article&id=344
Whiteflies:

Signs of an infestation:
Whiteflies are also sap-suckers. The top surface of leaves on infested plants become pale or spotted due to these insects feeding on the undersides of the leaves. Heavily infested plants will produce a buzzing cloud of flies if shaken.

The Whitefly life cycle is interesting in that the larval stage does all the damage. The larva will hatch and remain until it has quickly molted 3 times. Then it pupates and an adult emerges.

Controlling the Whitefly:
Insecticidal soap will take care of an infestation, as will the more toxic Diazanaon. Apply the soap (plus a wetting agent) to all parts on the plants, and both sides of the leaves. This will act to block the breathing pores and suffocate the pests.

Summary:
? feed by sucking plant juices
? mottled leaves indicate heavy attack
? may cause yellowing or death
? excreted honeydew may cover lower leaves, and black mold may grow on honeydew