My right thumb is swollen, red, unable to bend without difficulty and is warm to the touch. swollen, red thumb?

Cellulitis/fracture: Please have an evaluation soon. Possible causes include cellulitis or a fracture. An imaging study may be indicated. Monitor your temperature, and seek medical care at urgent care.

Need evaluation: If there was trauma to the thumb, then fracture is a possibility, otherwise it can be an infection or gout or another joint problem. Should be evaluated urgently by a physician. May need antibiotics ot further imaging and evaluation.