need advice here...what do u think?

ok so yesterday was my ex boyfriend's birthday...i havent spoken to him in 2 months but we left off on good terms so we're civil..i decided to text him "happy birthday john...enjoy ur day" and he wrote back to me a paragraph...saying "thank you dina!!!!! that just put a smile on my face cause i woke up with a terrible hangover and i now i have to clean up the mess from my house from pregaming." and he kept telling me about his birthday party...Anyway what do you think he was thinking when i text him happy birthday? do you think that he was happy to hear form me?