He is trying his best to communicate with you that he is not happy. Sounds like he is very stressed with the way things are and he is letting you know that. He is relying on you to give him a happy home but he's suffering silently and more than likely, that is the reason he hesitated even cuddling with you and that's very sad. Going to bed too early is also another sign that he is very uncomfortable and stressed in his tank. Stress alone can kill as it can raise the coccidia level way too high causing him to become very sick.
Are they the same size?
Snapping at the other one's spikes is a big sign that things are going bad. Please don't wait until one is attacked and badly injured or killed.
<<<< If money to buy another "proper" tank is the issue, you could split them up into two temporary 100-140 litre tubs (the stackable type that have relatively easy to see through sides and clipon lids), these are really good as rearing tanks for their first year or so and really easy to convert to lizard tanks with a couple simple tools and can be converted in a morning.
They hold the warmth in well, and are really easy to clean.
PM me if want know how I set up my 100L rearing tubs.
When he is in the tank, where does he spend most of his time?
What size is the tank? Hopefully it is big enough to put a divider in right now so that they both have enough room until they can each have their own enclosure.