I want to be strong psychologically but It's hard when you are as sensitive as I am...It seems so easy because I know exactly how they act but for some reason I still let little things get to me.. I have social anxiety to some degree but I know how confident I can be when I'm having a good time. What I'm asking is How do you just laugh at what people think about you and know yourself? any advice will be much appreciated.

You know what you need to do and that is to have fun ,for example when im walking to a club and need to get my energy level up for the night and losen up i might walk along the street and kinda play air drums with my hands kinda bop my head and have a song in my head and rocking out in my own world getting into a fun state before i even get there but its fun so find whats fun to you or try a few things.

Also try go out 4-5 days a week and get some social exposure and interactions with people even if its only for half an hour.
examples:mall,library,dance lessons,business chats with mates,language clubs,bars,clubs,resturant,gym,grocery shopping etc whatever just get out and get better consciously and consistantly.Also realise that life will probably test you even doing this,it might rain,the mall might be closed ,your car might blow up,you get sick,your too tired etc this is life asking if you really want this.

Other than that you need to get rejected over and over again and learn to handle it start online on chat/dating sites if your AA is bad and your still trying to get comfortable in social situations you can even be bold and force a rejection by being a douche but its part of not being needy and handling a no.

I know how you feel man in terms of psychological sensitivity, I was bullied VERY badly for pretty much my whole childhood, sometimes the negative beliefs do creep in but i've gotten good at filtering them out Fact is you have to condition yourself, if you get rejected use it as exerience instead of beating yourself up, reflect on where you went wrong during the interaction and in your next interaction correct it. As Tyler Durden says, hell if you approach enough most of this shite will auto-correct itself! Address all your problems and sticking points, face them head on and make an honest and whole-hearted effort to strip away the inhibitions and negative beliefs about yourself that you never asked for but were beaten into you by social conditioning. Ignore social conditioning altogether and never seek the validation of others, validate yourself instead. I'm not going to lie, I still have trouble following these pieces of advice but so far they've done pretty fucking good by me, Rome wasn't built in a day, it'll take time.