Heart break

Br
Yesterday, my boyfriend broke up with me, and his "reasoning" was incredibly vague. He said "I don't think this relationship is going how it should be going and I don't see it getting any better and I think we should just go our separate ways." 
And then, today when we worked together, it was so confusing. At first, he tried to avoid me, and then I gave him the rest of his birthday gift (his birthday is the 19th). His gift was a couple boxes of Girl Scout cookies. After that, he acted the way he did before we started dating. 
It was so confusing and I hate this. I just want answers and I want to not be heartbroken.