You should contact an electrician when you need any electrical done you have not had training for. Electricity is very dangerous, just because you are "comfortable" doing it doesn't mean you should. You should never be comfortable doing electrical because that is when you get hurt. You have to respect it and not be comfortable.
1. Maybe a rodent or somehow the home run to the circuit got chewed up or damaged in some way shape or form.
2. Adding new appliances that require dedicated circuits in your home or just maybe you have too much on one circuit and you are overloading the one you already have.
If you start overloading a circuit try plugging some stuff into a plug that's on a different circuit until you can have a new circuit installed.
Too many power strips can easily be fixed by adding more receptacles behind your entertainment center. There are a lot of fires caused every year by power strips being crammed full and plugged into each other.
Yes, we can change your existing switch to a dimmer, but might entail more than just replacing the switch as bulbs also need to be dimmable.
If your breaker is getting hot it definitely needs to be replaced. CONTACT an electrician IMMEDIATELY as there could be arching behind the breaker on the bus bar causing it to get hot or the guts of the breaker are going bad and are arching making it get hot.
1. When you plug stuff in it doesn't fit tight it is loose while plugged into the outlet
2. Any discoloration is a given.
3. If your outlet is back stabbed you need to replace it immediately as these cause multiple fires a year. back stabbed devices are where they strip the wire and it has slots on the back. You just push the wire in instead of curling it and wrapping it around the screw terminals and securing the screw down tight on the wire. backstabbed devices get loose connection between the crimps in the back of the device that the wire slides between and causes arcing. You can look these up on any search engine and see just how dangerous they are.