How soon is too soon to say I love you

So my boyfriend and I have been best friends for about a year and we’ve both had feelings for each other for a while but were too scared to tell each other until a few weeks ago. So we finally started dating almost a month ago and I definitely feel like I love him but I felt like it was too soon to say it so I just decided not to. But now he just commented on my Instagram post of us and said “Love you ❤️” is it too soon to start saying it??