Extremely painful nipples please help!

My nipples for the past week have been constantly stinging not just when my baby is latched,but all the time. Hes three weeks and we only breastfeed him. Ive tried hot showers, lanolin creme,changing from disposable nipple pads to washable and am currently trying tender care by medela; nothing is helping. We used a nipple sheild for a while to help with pain during feedings,now its 24/7.

Any mamas have any tips/tricks that might help? Ill try anything.

I do pump but i am pretty sure it is the right size. Havent had a problem till recently. Please help, going back to work in a week and trying to pump enough milk but its hard getting through just feedings.