This might help:
The sunflowers were initially painted for when his friend, Gaugin, was going to live with him. He painted it to decorate a wall in his yellow bedroom. Apparently it was pretty innovate for its use of yellow, and Van Gogh himself was considered influential for the way he painted stuff in a weird psychedelic way that pushed emotion onto the viewer. It was initially a token of gratitude and friendship from Van Gogh.
I don't know. How do you feel when you look at this painting? I feel like it's supposed to be a happy painting but... the curl of the petals and the twisting of the flowers make it seem a bit... bitter and thorny maybe. Van Gogh and Gaugin did have a lot of conflict and hard times between them. Also, the colour of the yellow should make me feel happy and brighten up the picture, but it makes it feel a bit... bleak. The whole painting feels a bit desperate and random, like I'm trying to look for something consistent and predictable and comforting from the whole thing, but I can't find it. I think maybe Van Gogh can't be unreservedly happy, even when presenting a gift to a dear friend. I keep feeling like the painting has pain behind it.
What do you think?