Is it premature ejaculation or just a way of life??

I'm 17 and I lost my virginity in May to this girl and I really didn't have feelings for her.

We used a condom and while we were doing it I really didn’t feel any pleasure and I don't mind as long as I please the girl we went on for quite a while.

Then I had sex with the same girl in August and I really didn't feel anything. Then she became my girlfriend and we had sex in early October but I ejaculated within 2 mins!

We did it again 2 weeks later and once I was inside her I felt the urge to ejaculated but I just held it in and kept going!...why is it that the first two times I was ok but these last times I was a little more weaker?

Tibor’s reply:

Sex is never same. There are times you feel like ‘exploding’; sometimes you can hold it for longer.
Condom makes you last longer (most of the time).
It desensitizes your penis.

The general formula is very simple. Most guys at young age come fast (we call it premature ejaculation).
But there is nothing wrong about it.

It does not mean you were any weaker. Sometimes we feel different. Depends a lot on sexual activity (how long ago we had ejaculation prior to sex).

If you mean premature ejaculation, that is very common and normal for adolescents. You will grow out of it.
There is a good article on it; site for teenagers