I've posted on here with similar concerns about my feet before. For you it's your head, for me my feet. It's that thing that I convince myself is stopping me from ever being considered female.
The other day work had a big party to celebrate being in business for 5 years. I had decided to wear a dress and sandal wedges, but was terrified that people would see my feet and instantly read me. I got so worked up about it that I nearly backed out. Various friends/family rallied around me to convince me that my foot issues were in my head, and I ended up going, wearing the dress, with feet on full display. And guess what; nothing bad happened. In fact, I just got compliments. I saw one guy who knew the old me and didn't know I transitioned; he didn't read me as trans, and so didn't recognise me.
I'd spent so long worrying about my feet I'd lost sight of the progress I'd made, ignored the positives in my appearance and most importantly let my insecurities put limits on my life. That's exactly what you are doing now.
I'm 5'8" and my head is 59cm, so only a tiny bit smaller than yours. I've never considered it to be a problem. If I started comparing that measurement with averages, obsessing over how my head looks etc, with the way my brain works I'm pretty sure I would quickly convince myself its a huge issue. You have essentially trained your brain to see things a certain way, so that to you, your head looks huge and you probably can't understand how no-one else can see it. Even when it's pointed out that it's the same size as some other person who passes fine, you are finding reasons why your situation is so much worse.
You need to start to address this, and seek professional help if needs be. From the photos not only do you look female, and perfectly normally proportioned, but you've made huge progress since those before photos were taken.
I'm never going to have the dainty feet I want, and you are never going to be small, but it doesn't mean you or I won't or can't pass. After I've recovered from my GRS I'm planning on seeking counselling for my body issues. I strongly suggest you do too. Above all, start trying to live your life rather than looking for reasons why you can't. You've had the strength to get this far; you have the strength to get past this as well.