...• Upsetting others around me when I fly. Seems there's always some anti-drone person around...
If there are others around, fly straight up to at least 200' and then out. At that height my MP is barely noticeable. Yours may be different so adjust accordingly.
...• The police showing up because of some complaint. Even if I'm doing everything by the book, I'm not a confrontational person, so I would quickly acquiesce if told by authorities to stop flying and move on...
Do not hover over people. It will creep them out and make them complain. If the police do show up, do not be confrontational - be informative. If they tell you to move then move. It is not an argument you will win.
...• Rules, rules, rules. Am I flying over too many people? Is this gathering of people considered a public event? Am I five miles away from an airport? Am I five miles away from the nearest helipad?...
If there are people around, fly high and do not hover over them. Fly around them instead of over if possible. Distance to airports is easy to determine with a map. I do not worry about helipads (of course I do not fly right next to one) but I also keep it below 400' and within VLOS so I can see a helicopter before it gets close.
...• Am I on private or public property?
• Am I disturbing someone's privacy?
• Is the drone too loud?
• Is it legal to fly here? Is it legal to fly above whatever I'm above?...
For the private/public property and legalities, do your homework. Check the area on a map. Read the aviation guidelines for your area.
For privacy and noise, like I mentioned fly high and do not hover over people.
...• Will I lose the drone? Will it flyaway?
• Do I have all the settings correct?
• Will I crash land and make a fool of myself?
Read and understand the manual and Go 4. Verify that your home point and RTH settings are correct. Go to an open area, keep it close, and learn to fly without looking at the screen. Once you are airborne, unplug your display so you can practice flying without Go 4. Then you will be more confident in your abilities when (not if) Go 4 crashes.
Learn to fly before you get into the camera settings and the "intelligent" flight modes. Pay attention to your battery indicator and start your return before it is recommended since the indicator is just an estimate and does not take wind direction and speed into account. Watch crash videos on YouTube. They will show you what
not to do.
The more you fly, the more you will trust yourself and your equipment.