yes you can but they may have to go in to fix your tubes or they may just watch the progress of the babies growth
yes you can, there are a number of women on this site at the moment who have had their tubes tied and are currently pregnant, you will just have to make sure its not a tubal, but otherwise you should have no problems
It depends. If it is in your tubes no you cannot. If it some how made it to your uterus you should be able to. But I would get a 100% on being pregnant first and talk to a dr to see what they reccomend if you are indeed pregnant and it's not a tubal pregnancy.