Its not just difficult, it is impossible. You can never be in control of it no matter what your efforts are.
Start ups that do wonderfully well, scale up to create whirlpools and have no clue to stop them. Therefore, they bring in energetic team members and expect them to swim effortlessly.
Take a step back.
Stop taking any further assignments until you have sorted out and prioritized (include capacity planning) your current projects. Define processes and keep them simple. It is difficult task, but as a leader that is the least your team is expecting from you.
And importantly, get yourself to believe that swimming in a whirlpool is impossible.