A: Calm is good, especially if it means unflappability and orderly progress.
Pupils can, and do, learn quickly from calm teachers.
Manage the impression you are making. Don't sit when you are being observed - move round the room offering feedback and advice. Stay visibly engaged with what the class is doing.
If timing is a problem, get a set of big, colourful, old-fashioned egg-timers. That'll make it fun.
As for "reading long passages and discussing them", ask yourself what you expect your pupils to learn from this. There may not be benefit in having decoded every word - might it be better to focus on key passages? Active reading - searching for patterns, style, understanding the author's craft - will encourage better readers. Get them to do the work - have them prepare the passages and comment on them to the whole class. If you've guided them to the points you want explored, and have set criteria for their presentations, they will probably learn more than they would by listening to you reading (or, heaven forbid, to unprepared reading round the class.)