Definately keep your documentation to show the reason you went late was due to an adjusting interest rate. Get the proof of satisfaction of mortgage from the lender.
What I would suggest is to rent for 12 months after the sale of your home. Pay the rent by check NOT CASH. You cannot prove a cash payment. Keep copies of your canceled rent checks.
After the 12 month time frame, as long as the rest of your credit items have been paid on time, you should be able to qualify for a mortgage, especially an FHA mortgage. I do them all the time for people with past bumpy credit. You just have to explain your past credit situation and show that you are a better credit risk now.
With a little bit of patience, you can own a home again. Next time, just make sure to get a fixed rate and with a payment in your comfort zone (including taxes and insurance), not just within your budget. I usually ask my customer what their comfort zone is for a payment and then translate that into a sales price so they know what price range of houses they can look at.
Good luck. I hope this makes you feel better.