'câinelu' does not exist.
It's câinele (the dog) or câinelui (of the dog / the dog's)
This is a tough question for a native to answer, about his own language. I for one, feel it does change towards the back of the word a little, but this may be too subjective to tell. I've heard many Romanian language speakers, mess up the stress when they added the article.
Also : 'vorbesc prea puțin română așa că vorbesc/scriu în engleză'.<= improved and sounds more natural