for about 2 weeks, usually every squat session.
Usually or always? If it's on and off, try your best to spot the differences between the days you don't get nauseas and the days you do.
Not sure I understand your question about my breathing.
There is a proper breathing technique for squats (and all heavy lifts, actually) and not everyone does it correctly. Holding your breath for the entire set, for example, could easily cause nausea. The right way to do it is:
1. Use the Valsalva maneuver (VM) and immediately start the rep.
2. As you come back up, allow your body to naturally regulate pressure in the form of a "hiss" or grunt.
3. After the rep is over, take several normal breaths before starting the next one.
It is worth mentioning that the VM itself may cause dizziness if you aren't used to it. However, just as your muscles adapt to squatting, your circulatory system will adapt to the higher pressures of the VM as well. After a while, dizziness should be very rare, only happening after extreme exertions (ie, new 1RM attempts).
bacon and eggs in the morning, rice and meat and veggies for lunch, dinner is rice and whatever, post-workout is a weight gainer shake.
I was interested in your diet for two reasons:
1. Low carb diets seem to cause dizziness after exercise, especially if you recently started one. It doesn't look like this applies to you though.
2. If you eat either too long before a workout or too close to a workout, nausea may result. Too long before is usually just low blood sugar and easily solved by having a snack (fruit works well) before exercise. Too close to a workout is pretty self explanatory and something that a lot of people struggle with. See if keeping 2+ hours between eating and squatting helps.