Overthinking and struggling

Well tbh just need a fair advice So basically my problem is that I do a lot of overthinking thats why I don't feel like myself. If I am facing a problem about my looks, money, dressing or confidence. When I have a lot of work then yes , I think about them but not in a dramatic way like what should I can do now but when the work get less then again same problems. I will think about all the dramatic things that happened to me , or why I am this way. I am a introvert and don't know how to ask for help to anyone. Sometimes this things and overthinking seems so much that I can't focus on any other thing. When someone comments on me , it feels so overwhelmed like I am the one in wrong and all the other things. What you guys do ,like in this situation make rules or don't think about this things.