Seem weird?

I’ve know my brothers best friend ever since i was 4 and i’m now 17 and he’s 28. I think of him as like a brother to me since he’s been around so long but we never really had conversations or actually interacted or anything. Recently we’ve gotten closer and he’s been inviting me to play games with him online, sometimes with my brother and other times with just him. he’ll play with me until 3-4 am. The other day i was in my room upstairs and he just opened my door and walked in, i thought my door was locked and I didn’t know he came over and i’m not sure he even knew i was in there either but he still was planning on coming up stairs and going in my room. He has never done that before and i found myself extremely uncomfortable. He just asked what i was doing and then just stood there for a minute and then shut the door and left. When he comes over sometimes he will pick me or my sister (18) up and pretend to wrestle us or just just jokingly carry us on his shoulder. he’s been doing it for a while now and i always found it weird and it made me uncomfortable. he only does it to me and her. I just have a bad feeling about all of this and i’m not sure what to think or do. Am i just overthinking and the stuff he’s doing is just normal?