What for you use mobile 24x7?
Can't you change your lifestyle?
Pain could be due to accommodation adjustments, or lack of it. So stop or minimize mobile use. Use for attending calls, quick check of mails, messages.
Thread like mucus could be due to allergy mostly, but without any itching, I still think it is due mobile use. Excess use cause drying, and mucous secretion is due a helpful reaction of body to keep eyes moist.
But why are you pulling mucous to the extent of making it (spinning) it into a thread? Do not do that. It will be cleared by itself, by eye blinking action. It is pushed to the corner of eye, nearer to nose, and when you clean the face it gets washed off.
Next Steps
can't rule out allergy.
if possible eye specialist opinion is better.