1) You must have missed the brief where evidence was uncovered that the Obama Administration spied on foreign country leaders, like Angela Merkel's cell phone, spied on former UN Secretary General, Bank Ki-Moon etc....
https://edition.cnn.com/2015/07/03/p...ion/index.html
So to answer your first question. Big FAT YES!
2) Again have you been sleeping?
Andrew McCabe, Deputy FBI Director who was fired because he lied, under Oath several times, (Lacked Candor) his wife accepted Donations from a Democrat. He is supposed to have sat on information that thousands of more Clinton emails were found before the FBI announced they were re-opening the Clinton email investigation.
Two Agents who fell in love with each other, Peter Strzok and Lisa Page, which breaks FBI protocol, were texting each other like crazy and a trail of texts discovered showed their political bias towards Hillary, such strong bias led to a very 'infected' investigation, where they decided to clear Hillary Clinton of wrong doing but decided they would act against Trump if he won, re their "Insurance Policy" that they texted each other, about that they had discussed a plan in "Andy's office", that's Andy McCabe.
So to answer number 2. Yes they acted Politically. As Trump as accused them of being so, they were tainted under it's former leadership.
As for 3, Trump has repeatedly said he and has campaign were spied on, he raised it weeks after being inaugurated that Obama admin spied on him. He was laughed at and shrugged off as just being silly, he is having the last laugh now.
Remember he tweeted this last year.....
So he has not just suddenly been claiming he was spied upon...