What Causes Bloating Of Abdomen Along With Burping?

My last meal for the day is at 9pm at work, i eat moderate meals and always drink one big glass of mixed 1/2 water, 1/4 cranberry juice and 1/4 orange juice together with my meal. I will not eat anything when i go home at 1am. I take my night pills before i go to bed, 1 baby aspirin, 1 gluvastatin and 1/2 chlorthalid,
When i lay down in bed that is when i will feel the fullness on my upper stomach, i think burfing will help but i cannot force my self to burf.
Please help
Thank you so much