why is my usually independent sleeper begging for cuddles?

my dog has started "asking" for cuddles when i go to bed, sometimes i will let him on the bed next to me laying on his side or back and he gets belly rubs for about 5-10 but this isnt usually often. recently hes been coming to the side of the bed at night and looking at me till i let him on or say "on your bed" also when i do let him on he has been staying laid with me for alot longer when he used to get up and go back to his bed seemingly happy with and had enough cuddles. im unsure if i should be calling the vet as he hasnt really done this before. hes a kelpie x collie desexed male 4 years old. is he sick? is he just growing up and calming down? am i worried over nothing? other info that might be helpful, hes always been very dependant on me (at the same time is protective), hes been having more dreams then i had noticed before.