quick question here: I started playing guitar a few weeks ago, and I keep struggling to play some chords, such as G Major, because of my pinky finger. Every time I press the high e string it suddenly snaps into an uncomfortable position and also prevents me from quickly transition between chords. Sometimes, even the ring finger gets in this position too.
Question is maybe how do I stop it happening. For starters, only use fingers on the top and bottom E and the A strings. You've only just started, your fingers aren't used to the position and pressure, make the job less by 25%. there's no real need for a finger on the B string. Keep things as simple as you can for now.
Sometimes our fingers actually have to get into that 'collapsed' shape to play certain chords, so it's not necessarily a bad thing. Pressing closer to the fretwire will mean you don't have to press as hard, which'll help as well.
Changing chord shapes is never easy, and will come with more experience, bearing in mind that sometimes you'll need a couple of different fingerings for the same chord. get used to hammering the whole chord on, as this will mean all fingers arrive at the same time, eventually meaning quicker changes.
Judging by lack of blood in your fingertips, you might like to press down less. Finger strengthening exercises are a waste of time - time which can be used better practising the guitar!
My experience suggests that scales and exercises that heavily involve the pinkie may help.
I used to get your trouble in my banjo playing. For certain chords, my pinkie would land in the shape you show. It felt like my pinkie finger joints were "cammed over," and a lot of time/energy was required to get them out of that angle. I never discovered why, and my instructor didn't have any ideas.
For me, the cure came unexpectedly after I started doing scales that required the pinkie to be heavily involved. I was very demanding of myself that the pinkie should be used wherever a scale demanded it, with no cheating by letting the ring finger do the pinkie's job. It was unpleasant because my pinkie did not want to be used in this way. My pinkie lacked strength to such a degree that the muscles in my arm would ache when I forced the pinkie to be used. But I persisted, and after the pinkie got strong enough and agile enough to do its duty when playing scales, I noticed that the chords that gave me pinkie trouble no longer did. The pinkie no longer feels "cammed over," it doesn't look like your picture, and it's quicker to change from the chord shape that gave me so much trouble before.
I don't know why pinkie exercises helped my chording. Perhaps increased strength in the muscles that work the pinkie caused this improvement. Perhaps it's just that my brain got better at using the pinkie.
You might try looking at how you are positioning your thumb on the rear of the neck.
If you position your thumb near the centre of the neck as a classical guitarist would, it will enable you the arch your hand more. This should allow you to avoid this type of reaction. It may feel awkward at first, but you will find that this left hand positioning makes for much cleaner fingering.
If you are positioning your thumb so that it appears near the top of the neck or over then neck as most rock guitar players do, then you may have less freedom to maneuver your fingers over the fretboard.
There are a number of ways of fingering a G chord. My preferred method is to use the middle finger on the A string (2nd fret), ring finger on the low E string (third fret) and pinkie on upper E string (third fret). For most musical purposes, I think the chord sounds better with the B string open, and fingering it as I described will enormously ease a transition to other chords.
To move to a G7, simply put the index finger on high E first fret and raise the pinkie. For C (move the middle finger and ring finger to the D and A strings, respectively, while placing the index finger on first fret B string and raising the pinkie). Transitions to D and D7 aren't quite as simple, but my preferred fingering for those puts the middle finger and ring finger on the second fret of G and upper E strings, leaving the index finger or pinkie to take the first fret (for D7) or third fret (for D) on the B string.
Although I often end up with a back-pend on the pinkie on some other chords (in fact, I'll often use the pinkie to fret both of the two upper strings), and I don't see it as a problem, I think you'd find the pinkie would naturally be straight vertical if you reach to the sixth string with your ring finger. While that may be a stretch, it will make transitions to other chords so much easier that I really can't imagine playing a G chord in standard tuning without putting the ring finger on the sixth string.