Exercise alone will not help with weight reduction.
Hope you are eating the right foods at the right time - irregular mealtimes and inappropriate diet could cause nausea.
Irregular bedtime and stress can increase it.
Have the reasons for weight gain analyzed so that you can move forward?
Muscle aches could be the result of exercising without warm up and insufficient fluid intake.
Next Steps
Warm up before exercise, Stay hydrated before, during and after, Cool down after exercise.
Plan your diet and mealtimes.
Manage your stress.
Health Tips
Don't overdo the exercise.
It needs to be gradually, progressively increasing in intensity and duration.