It’s best to trim off the drooping or dead flowers so the plant can put its energy back into healthy growth. From what you’ve described, it sounds like the potting mix has become hydrophobic, meaning the water runs straight through without soaking in. That’s a good sign the soil quality needs improving. I’d recommend repotting your Gerbera into a slightly larger pot using a fresh, good-quality potting mix that holds moisture better. When watering, aim to keep the soil just slightly moist and only water again once the top has started to dry out. Be careful not to let it sit in soggy soil, as overwatering can be just as harmful as letting it dry out completely.
Here's a helpful guide: How to grow and care for gerberas.
Please let me know if you have any questions.
Mitchell