My LMP was March 1 I was having sex with my Boyf from march 10-18 and we broke up before he left I had sex with an old friend on march 27 and I found out I was pregnant on April 6 I am now 15weeks pregnant who is the father

The ONLY way to establish paternity would be a DNA test AFTER the birth as the dates are too close to even guess.

Whomever's sperm fertilized the egg. And the only way to tell is with a test AFTER birth.

The ONLY way to establish paternity would be a DNA test AFTER the birth as the dates are too close to even guess.

So even if my period was due 3days later it could possibly be the old friends? And the doctor said my conception date was around the 15th and my ovulation was between the 11-16th I believe .

Pinpointing conception dates is an inexact science.

If you want a basic idea try this...
Conception date calculator (http://www.pregnancyandbaby.com/tools/articles/942801/conception-date-calculator)

If you want a basic idea try this...
Conception date calculator (http://www.pregnancyandbaby.com/tools/articles/942801/conception-date-calculator)

This calculator can give you "Probable" dates but then only if you have a regular period and can pinpoint the exact day of ovulation.

In other words, trying to pinpoint a conception date is an in exact science and can only give you a range of dates and only based on the accuracy of the data you have to use in the calculation.