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Well, it would have to have a partner planet or some other large body in the system to maintain the eccentric orbit it has, otherwise tidal forces between it and its parent star would've circularised it over time. It needs those gravitational tugs to keep it in that elliptical orbit (which is less eccentric than Mercury's).
Two days isn't all that uncommon amongst these close in planets. There are a number around that orbit their stars in even less time...WASP 18b for example.
This particular planet does have some tidal effects due to it's closeness to the star, but not enough to adversely affect its temp...remember it orbits a small star (an M dwarf).
No, because Saturn and Jupiter formed a long way from the Sun...way outside the ice line and a long way from all that heat and solar activity. They did change their orbits as they were forming but the accretion disk around the Sun was neither massive enough to create enough drag on the planets to slow them down, nor did it last long enough to give these effects time to take hold. After the little game of "billiard balls" finished after their formation, they settled into the orbits they're now in. In many systems, this process keeps on going till you get the situations we see.
These planets do have initial histories in common, but it's what happens after they form that is important. What occurs around the star and the environment that is present, which determines the fate of the planet. It all depends on a lot of factors, least of which is where the planet initially forms and how that occurs. That builds the planet...then it's up to the gravitational and other dynamic conditions present as to where it may orbit eventually.
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