Hi Guilherme!

I checked out your website and it looks really good and I don't see anything bad about it. However, I used the backlink checker of Moz and saw what's going in with your websites backlinks

Apparently, you have more than 8,000 referring domains which looks really unusual and on top of that, you have websites linking to you with 30% spam score and above which could be a heavy factor on why you have such a high spam score.

I'm not from Moz so I can't say how fast they update the spam score, but my advice would be checking out their backlink checker, check out the bad links linking to your website and use the Google search console to disavow these links.

Hope it helps!

As far as I know, Google will automatically pull up the Header 1 as your title and your meta description will be the first 160 characters of your blog post/page. Its more ideal to install a plugin like yoastseo and set up the title and meta description manually every time you create new pages. But if nothing is set, Google will automatically generate that for you. It can be bad for your on-page SEO if you have overly long H1 tags but it won't be too much of an effect. You would see it as an error every time you use tools to audit your website as well as not having a proper meta description.