Thoughts on my personal websites design mockup?

I had originally created a website based off of the one found in the "How to build a website" course, while that did the job, it was kind of plain. So I decided now that I feel more comfortable with responsive design and stuff, I would make a custom one. This is the design I came up with: https://i.imgur.com/mkNGr70.png

As you can see, its a single-column layout, with blocks of content-specific portfolio items. (The very bottom of the page will have CONTACT and such) I plan on adjusting how many portfolio items appear in each block depending on the screen size, from 2 to 4 to 6 and so on. Right now, I will have "Web Design", "Photography" and "Videography" (My YouTube channel I will someday be active on) I originally sketched a wireframe, and then designed this in Photoshop. I thought before I write a bunch of code, I would get peoples feedback on the design. I know static-front-end stuff is hard to make look "alive", so I plan to add some small animations when hovering over portfolio items (Like, said item fades out and instead shows a description) or something. As you can see also, there are arrows for a slide-based system to display more items. (I am really not sure how to do this as of yet, I am assuming I'll have to hack with a jQuery plugin to figure it out however.)

Please leave feedback below! I am open to ideas and things people may think it needs. This is one of my first page mockups in Photoshop, so don't judge too much...