Don't let dreams become nightmares, calculate risks you have to take accordingly.
Hard work is necessary, be smart and know how to delegate tasks effectively if you aren't good at what needs to be done.
Take a walk. Movement itself in the physical world translates to increased blood flow to your brain and a faster stream of thought. Meditation may also achieve similar goals.
Most businesses fail within a few years, most successful people fail several times. Hopefully you are in a country with strong social safety nets that allow for risk-taking, or your social network is strong enough to support each other when you reach for newer heights.
The time value of money is huge, just look at how profitable renting out delegation is.
Networking is the most important tool in the modern business world. Networking is everything. Do not burn bridges and elevate your social circle.
Don't waste too much time on a sunk cost either, if it is sure to fail then write it off and use that experience to avoid such a path in the future.