lol no, i'm not psychologist, but usually if i have a problem i find solutions for it, find the cause of it, do my own little research and testing and see the results. I just keep trying different ways to find the good result to improve myself. Staying at home a lot does give an effect to your confidence level. It is more about the mind than the body. Because, like last year, it was my SPM year, during near the trial SPM exam and the real SPM exam, a lot of SPM students dont wanna go out that often, parents won't really let me go out also, that time most of the time just stay at home, when go to school, most of my classmates dont really talk as much as we did like during early of the year, cause many wanna do revision and study (boring!!!) and we all need to do that actually, seriously, at that time, my confidence level that was from top 10, went down big time and it affected me until like a few months after SPM. Then when I started working part time job is when I started gaining back my social skills and confidents level, but the part time job was kinda suck too cuz boss damn strict, must do a lot of work, don't get to socialize as much as i wanted to . But now after months of improving myself and practising, I'm back to normal, infact I think I am better than last time now, because now my voice really loud already, and now I really scare if I talk loud people will think i'm scolding them lolz  . Now i'm finding a way to lower down my volume, so far I'm still finding a way to control it cuz my mom say when I talk softer damn soft until she cannot really hear, when talk louder DAMN loud lolz. When go to cinema, a woman turned around and gave me and my friends the "SSSHHHH!!!" 

PS: I advise you all to go out at least once a week, better if go out with friends or go out to meet people.  . It's good to practice or know some sales knowledge also because good salesmans usually have great communication skills and usually good salesman knows how to communicate well and convince people also.