Help with Training my Thoroughbred!???

My horse Buzz is a 6 year old thoroughbred gelding. I've been getting back into working him, since he was off for a while. (he had strangles :'( not fun). I also just got him this summer so I haven't really had a good long ride on him yet since he's been off. I'm still trying to figure out all of his quirks and stuff! I'm still getting used to the fact that his stride is so much longer then horses i used to ride, so it feels like he's going fast when really he's not! I'm also a bit of nervous person, so sometimes he can feel it. (My recent fall didn't help my confidence either. I'm always worried he'll bolt again) I'm worried that my nerves will make me never be able to ride him confidently. I am REALLY confident with groundwork and lunging, it's just when I get on I tense up. Does anyone have any tips on confident riding and controlling faster horses? Any websites or videos would be greatly appreciated!