I've been investing and buying stocks for a long time and one of the most difficult things I have had to learn is to trust my own stock picks. In fact, it is something I still haven't been able to do and in the last couple of years it really cost me.

Sometime last year I got interested in shorting Netflix. I don't use them myself and after researching their service, decided against it because most of the movies that are offered are old. If I have no interest in signing up, I thought maybe others felt the same way. About this time there were also many articles from various sources saying the stock was overvalued and after really thinking hard about it, I agreed with them.

So, I shorted them at around $200 sometime during the beginning of 2011 and watched the stock daily. I watched as it went up and down but there were pretty much two ups for every down. The paid was bad as the stock passed $250 and kept going higher. And higher. And higher!

I just didn't know what to believe as I felt I was right about the stock but I just couldn't take the pain of losing more money every day as it continued to rise. Finally I gave in around $290 and covered my short for an ugly $90 per share loss. I was sick....but not near as sick as I would soon be.

About a month after covering my short I watched in horror as what I thought would happen all along did: the bottom fell out of the stock and it lost more than two thirds of it's value in a little over 4 months. THAT was what I was betting on before and so not only did I lose a big chunk of money, I wasn't around to reap the rewards.

This year I have had another very disappointed stock result when I bought Nokia at about $3.30 after it came down from the 5's. I knew it was a gamble but they had the Lumia phone with the Microsoft operating platform and I just didn't believe that this company would totally fail. I felt they would ultimately do well in the 3rd world countries and in places where people couldn't afford a pricey iPhone.

Well, unfortunately for me the price continued to go down as I read article after article from slews of analysts saying that Nokia was on the fast track to bankruptcy. There was just nothing good reported about Nokia and the price kept going down until I decided to at least get something back and I sold at $2.01. Another big loss for me but I felt good about it after the stock went down further to $1.69.

So now I sit here writing this and watching Nokia hit $3.26 after going straight for all of August and had I just held on a bit longer I would not have sold and almost been at the break even point today.

Is there a moral to the story? I'm not sure but if there is one I think it is that I need to trust my instinct a bit more. These are two instances where I took a big stock loss and had I just waited a bit longer, would have been proven correct. No matter how much experience you have buying stocks, how much money you have, or how convinced you are that you are right, it is very hard to hold on to a stock when things don't go your way.

In these instances the pro's would say I was "early" but "early" doesn't pay and instead can cost you. I don't feel I was early, just a dummy.