Deadlift Injury

Hi Guys

So around early december 2008 I was doing my deads (Ive been working out on and off for about 3/4 years) and whilst lifting the weight I turned my head to the right (dont ask why) and I got a faint "line" of pain going doing my lower back. See image below (pain area in green with white outline):

http://img13.imageshack.us/img13/2221/body1.png

So I ignored the pain and finished my set thinking it was a muscle pull and should heal itself within afew days and it did (or atleast it appeared as such). So a week later I was doing squats followed by military presses, the faint pain came back so I only did 2 sets instead of 3. About half an hour later I was running some errands and I leant forward to get my clothes when I felt a burst of pain in the green area highlighted above. Its was like someone stabbed me in that area. I didnt fall to the ground but I was stuck in that position for like 10 seconds, after that I could only take baby steps. Anyway, after some sleep the next day was much better, I had around 60/70% mobility, I could take slightly larger steps and within a week I could walk properly although still not 100%. Now, its been 4 months going onto 5 months and sometimes I still get pain in that area. If I lift something that'll put stress on my back (like my nephew!) or sit in a strange position the pain comes back. It was getting better and I hadn't experienced any pain in months 4/5 of recovery but last week I lifted my nephew and the light pain is back. Its been on and off since then.
I did goto my GP, he checked me and told me that it isn't too bad and that I'll need physio (this was 2 months ago). However, I missed my appoinment but since it was getting better I didnt bother rebooking.
For the information of the reader, the doc told me to lay down on my back and lift my legs as high as possible, that was ok, I experienced no pain and lifted them both very high. He also pressed areas in my back to check for pain and there was no pain.

Here are some other points which may help you guys:

1. During the first month of the injury I was on the train sitting down, I got up and as I walked out I noticed the joint in the upper part of my leg was clicking/popping everytime I walked. The happened for like 100m and then it stopped. Never got it since.

2. I am a software engineer therefore I spend alot of time on my computer chair (7-8 hours) with breaks. I do try and maintain good posture etc

3. I have noticed the areas of pain have slightly changed. I now get light pains in my leg too, see image below (areas of pain coloured in red with white outline):

http://img4.imageshack.us/img4/9881/bodyh.png

I hope someone can shed some light on my problems.