Lemons take forever to ripen and turn from green to yellow. Most lemons you buy are picked and shipped while still green.
I’d say just keep on watering and feeding. I keep my lemon tree kinda root bound, and trim it back periodically so that it will continue to fit in the space that I have to grow it. I was thinking that maybe it thinks it’s dying and is desperate to reproduce.
Otherwise, there is no reason for it to bloom so prolifically. LOL
Your lemon is in a container? Mine is too. Actually, I have two in containers, the other had a bunch of flowers that budded into little tiny fruit, then all dropped off the plant about 5 months ago.
A friend of mine in Ohio has a Wysteria tree for 20 years, and it never flowered , and she couldn't figure out why it never flowered.
I told her that the plant was 'too complacent', and had no stress.
I told her to hit it with a bat, or a 2 X 4 board, about seven or eight times ; that year it flowered profusely for the first time .
Sometimes a little stress is needed to motivate plants to flower ,set fruit , and set seed to reproduce .