First prep race for next year's tri in London

I did complete my first 10k (in London) today and didn't do too badly. I am preparing to complete next year's London tri with 1.5km swim, 40k bike, and 10k run sections. Given today's performance (1:04:37) I think I should be able to do it since I didn't really prepare for this race and by next June will be quite a bit lighter than I am now (currently 243 lbs). The one thing I figured out is that I need to spend some more time on developing a proper running technique to become more efficient. Other than that I am getting stoked about next year's tri. Going to have to get some ice for my knees now - they are killing me, though I am sure carrying a bit less weight will decrease that significantly come next race day.

In case you're getting ready to do a race and need some encouragement this is what I can offer: I've decided to do this run 30 days ago and since then ran about 10 times on avg. 3 1/2 km per trainings session (all on treadmill though - which I don't recommend). Anyway, based on the prep time every one I know told me there's no way to complete this. Well, I did. And I am not anyone special and IF I can do something like this so can you. Whatever you set your mind on you can and will achieve if you are determined to put in the work.