Penn State accepted me last summer but I went elsewhere and I regret it...would I need to apply all over again?

I applied to transfer from my cc to penn state last summer and was accepted but I chose a different university. I now wish to attend penn state instead. Is there some sort of procedure for this or do I need to apply all over again? Im a little worried because my grades dropped a little bit this past year and I got a couple W's in the process. I think I had about a 3.4-3.5 at the cc when I applied to transfer last summer and this past school year at this other university I finished with a 3.125 but also landed a solid, major-related internship during that time which might help my cause. ALSO, its almost july...is it too late to apply for the fall term? I heard it was much harder to get accepted into the spring semester than the fall semester. Is this true?