Inattentive type?

I am really quiet and I hate being quiet so much sometimes. It’s not that I’m shy, I don’t think, I just don’t have anything to say. When I look around, it seems like everyone makes friends so fast and everyone is laughing and having a good time so easily. I just don’t understand how they do it. It comes so naturally to them, and it seems like if I confronted or asked them about it they’d just say something like “Speak your mind!” but the thing is I just feel like I don’t even have a mind to speak. I feel so blank and boring.

I'm the type of person that tends to get easily bored when someone else is talking to me. I have difficulty paying attention in conversations - especially those that involve topics I'm the least bit interested in. I don't know if I should take this as having a short attention span, or the fact that I'm sometimes a little too absorbed with "me" and fail to be receptive to others' views and stories. One thing is for sure - I hate mindless chit-chat.
The thing I hate most is that I never remember movies immediately after I have watched them!

As a result, I usually don't provide immediate feedback, if any. Sometimes when people like my grandma talk to me (ask questions, ask for opinion, etc) they end up asking "Do you even understand what I just asked you?" Sometimes I even find myself proceeding to doing something else without even responding to them. In class discussions, for example, I usually do not raise my hand unless I really commit myself to do so. During the lecture, I usually drift into other worlds of thought. I really do feel that I have a REALLY short attention span, but I'm not sure exactly what it is. At times in high school when we had breaks in class, instead of sitting around listening to others in class chat with one another, I preferred to stand up and stay in the restroom until the break was through.

I've noticed that I try to distance myself from relatively large groups of 4 or more people, especially if I don't know most of the individuals. I shy away from topics in conversations that either I'm not interested in, or that I have no practical knowledge of to apply to the conversation. Additionally, if i'm talking with a few people, and then someone comes along and takes center stage, I might withdraw a bit. Once it's evident that I'm not as active within the particular group (others focused on one main person or persons), I'll step away and let the others do the talking. Throughout my early life, I've realized I've been associating myself more with the low-key guys and girls who care not to step in the spotlight. It makes me feel more comfortable about myself that I'm around people who are more genuine.

Lastly, I also have this tendency to like to go against the grain. In order words, I like to do things that separate me from what other people do or expect from me. Sometimes if everyone in my house heads out somewhere where I don't feel like tagging along to, i'll wait until they all come back and just leave without notice.

I want to improve on some of these areas, particularly being more talkative and receptive to others stories and not getting bored by them. I also want to be more alert and ready to deliver feedback once questions and statements are thrown my way.

Scanning your post quickly, your inattentiveness and shyness seems to come out in social situations. What about other areas of your life? How about when you're trying to accomplish tasks? Does your boredom and inattentiveness kick in those situations?

It isn't just being bored with social conversations and being overwhelmed in crowds that makes for ADHD. Sure those situations may bring it out more, but it sort of goes in other areas too.