Answer:
Both Jesus and God are 'Lord'.
The word 'lord' is merely a 'title' which can apply to humans also.
The Hebrew word (translated into English as lord) simply means 'owner' or 'master'.
God is our owner, since he Created us, and thus owns us.
And Christ Jesus is also our owner, since he purchased us with his shed blood.
Both God and Jesus also have other 'titles' that are similar. God is called 'our Father' (Matt 6:9) since he created us. Christ Jesus will also be called 'eternal Father' (Isa 9:6) since he will resurect the dead. Since he gives them life by resurecting them; and since they will receive everlasting life, Christ will always be our Father, thus becoming our 'eternal Father'.