It's fine. All Gundams have a similar head/chin/v fin thing going on, but not exactly like the RX-78. It's just a design thing.
As gor an inuniverse reason why the heads look similar, many U.C. prototypes in those shows took after the style of the original Gundam, I guess as an honor thing. But the one you were looking at was in an alternate universe show, which has no rx-78.
I saw a cool looking Green Gundam posted but since the head looked exactly like the RX-78 (I'm probably wrong and my lack of familiarity just puts me on the same level as a grandma who thinks every giant robot toy is called Optimus Prime), so I was wondering if there were any really super unique Gundams that don't really have RX-78ish heads. Then again, there's probably a reason in universe why most of them look like heavily modded RX-78s. And then again I'm not sure how "different" a humanoid robot in that style can look.
And if it still seems like an odd question, I've always been drawn to the "different" robots. I don't like the Liger Zero but I think the Rainbow Jerk looks awesome.
I take AP classes. It's not really the content of school that makes me feel out of place. It's that I mainly miss my friends who are now off to college