Exercising treaty rights for less than 5 years - when pr?

[ninkas]

Hi there
I truly hope you will be willing to help me as I'm a little bit confused right now.
That's my timeline briefly
2005 - arriving in UK
2006 - had my eldest child
2006-November 2012 self sufficient- no csi
15th November 2012- 12th December 2013 self employed
Rc received in the end of October 2013
13th December 2013 till 15 July - employed part time 25h per week
16July 2014 - 15 April 2015 on maternity leave
16 April 2015 up to date employed by the same employer part time 25 h per week

Now my question: am I able to apply for pr right now? I read about accepted applications for pr with gaps between employment less than 6 moths. Does it apply to me? Can I write a cover letter explaining that I was preparing to open my own business before I actually registered as self employed?
Thank you in advance