I would put this worry out of your mind.
Here is a good reference from the CDC on this extremely rare, but terrible infection.
In that reference you will find sources of the ameba, and you will also find that between the years 2003 and 2012 there were 31 cases in the US. RARE, rare, disease.
You will also find that the incubation period for which this infection to become apparent is roughly 5 days with 7 days being the outside number at which one would develop symptoms.
Since you are getting better from your cold, and since the odds are so small to begin with, I think it is very safe to say that your chances of getting this infection at this point are roughly zero.
I would not give another minute to worrying about this.
If you have questions about my answer, please ask them below and I will respond.
Thanks for your question. Positive feedback is always appreciated.
Thank you so much.
I'm prone to the occassional bout of anxiety, which in this case I believe came on after being sick all week and stuck at home unable to work out (it's been about a year since i've been sick!) and just sitting around thinking.
I thought I should seek out some peace of mine before the psychosomatic symptoms started appearing.
glad to help.
ask for me anytime, simply start your question with 'for 911doc'.