Soon to be 13 year old wanting to sleep in our room most nights. Unsure how to handle this the best way possible?

My husband and I have four kids. A 14 year old girl, 12 year old boy, 2 year old boy, and 5 month old girl. We have a 4 bedroom house. The older two sleep on the same level in separate bedrooms across from each other. The toddler sleeps in one of the downstairs bedrooms and we room share with the baby in the room across from him.My 12 year old (13 in March) is a good kid. He plays hockey and baseball. He gets straight As. He has a lot of friends and goes to sleepovers. Very average preteen boy things. He is open and talks to us a lot.About 3 weeks ago he started coming into our bedroom in the middle of the night asking if he could sleep on the floor in our room. It was late and we didn't ask why. We told him he could. It was probably a mistake because this has been happening over and over again. We told him no and he got very angry. He started yelling and asked if we cared about him. We both got up and had a conversation with him about it. He said that he's been having bad dreams lately and just feels more comfortable sleeping with us. He said he can't remember the dreams but wakes up scared in the middle of the night. That is when he comes downstairs. We have tried getting him a nightlight and leaving the door open. His sister has been leaving her door open with her light on as well. We have let him leave his light on. We have tried white noise.At this point I don't know what else to do. Do we take him to the doctor? He seems to get bad anxiety when we tell him no and its not in a way I have ever seen before. We tell him no all the time and he accepts it, even if he sometimes pushes, but this is different. It's like he is genuinely and truly afraid of something but he can't explain what.He is a normal boy during the day. Laughing and joking around. He had friends over last night and was doing great. He went to his bed to go to sleep but woke up in the middle of the night and came to our room. We reached out to his teachers this week (without revealing details) and they say he's fine at school. His hockey coach couldn't think of any issues. via /r/Parenting http://bit.ly/2DLGMco