It should not get hot - at all.
If it gets hot even if you don't use pin D5 (didn't read that part too well before) it's pretty seriously fried and likely to overheat sooner or later. You may also get all kinds of other unexpected side effects.
Last question: will ESP8266 ESP-07 (I need external antenna) chip work if I solder it on D1 mini board?
No idea. I think it's an ESP12 module that's on the D1 board. There may be more wrong with it, of course.