Why are you bothering? Seriously, you are not together that long and he has already given you many reasons to be weary of him and there are so many red flags screaming you cannot trust him. If I was with anyone less than a year and I felt the need to ask for relationship advice during that time-that would be enough for me to go and find someone better. It should not be this complicated.. and you shouldn't be confused about anything.
Also he should have no contact with any exes. I don't understand why anyone would keep in touch with an ex. Maybe its okay to send a quick text every now and again saying "how are you" but other than that, there should be no contact. And men do not pay that much attention to a women unless they have a hidden agenda. Most men do not want to be best friends with a women-they have there male friends who they find far easier to understand and then they are supposed to make time for ONE special girl.
Its your choice but I think you should follow your instincts. You already smell a rat and you know this situation is not right..