...questions...
Yes.
All boil additions are written that way. How long the item needs to be boiled for. 60,30,15.5,0 mins left in the boil.
First wort hopping is hops added to the first runnings of wort before the boil begins. Edit: question the recipe as m00ps said. Usually FWH or 60 minute addition, not both. Pointless really to do both.
With IPA recipes there are often lots of after boil additions or additions at flame out 0 minute boil. Hopstands, whirlpooling and hop bursting are all things to explore. I don't make many IPA's so am not the best to offer advice.
Northernbrewer have a great clone recipe of Bells two hearted. I can't add the link but if you google Northern Brewer Dead Ringer recipe it will get you the PDF. Then just scale it to your setup and get the ingredients. It is a tasty IPA.
By all means wait to make the next beer but just remember if you've bottled this one you have 3 weeks to wait for a taste. 4-5 it will probably be even better. Then you brew your next one and you'll have 4-5 weeks wait between brewing and tasting. Thats 9 weeks from now to compare the two beers. Get a pipeline going, brew as often as your time, space, equipment, budget and desire allows.
With each batch make improvements to your methods and skillset, try new things. Refine as you go. Once the pipeline is well stocked you can relax.... phew.. It's great to have as election of HB to choose from.