How do you get rid of feeling awkward?

I'm 22 and I still feel this awkwardness that I've had my whole life. I went into a store earlyer and immediately felt uncomfotable I felt sick to my stomach like I make this weird awkward face and my lips don't feel at ease. I just look awkward and uncomfortable. I've been told I'm not a bad looking guy and I believe it but knowing that doesn't help and talking to myself while I'm there doesn't help either. I kept thinking of this time I overheard this one guy say I look squirrely and my freinds always make this weird face and it comes off like their trying to immitate me just joking around. So I'm convinced I look weird but even if that's not true I can't get a grip of myself when I start feeling awkward and I'm convinced people can see through my facial expressions that I look uncomfortable and it brings unwanted attention to myself I just can't look at people because I don't want to freak them out. I was told to relax and tell myself not to think about it brfore I walk in and it doesn't help. Should I accept this is how I'm gonna live my whole life? Or is their hope that I could get over this and how do I do this?