Hip Flexor Injury?

Hi all,

I'm looking for some advice.

When I was a kid, practising karate, I injured my leg. But as any other kid, I limped for a while, waited for it to go away, and got back to it...

Never bothered me again, but I could feel something there when I went for long walks.
I felt it in the hip flexor area (not a pro though), and in the upper part of my glute. Left leg.
10 years went by, and one of these days I got injured in the hip flexor (I think) while stretching and aggravated it at work lifting some loads. Could hardly walk.

I went to the hospital, and I was diagnosed with a groin strain, sent home to rest. I did so for nearly 2 weeks. Some ice. Pain gone.
After researching for a while I though it was more likely for it to be the hip flexor, but once again, I'm no pro...
It didn't hurt while squeezing my knees against each other. The pain was when I lifted my knee (sitting position). Stretching (quads) my leg was OK as well. Just lifting my foot from the ground (with leg).

Now the pain is gone, even if I do "normal hip flexor stretches", but it does hurt when I stretch in the following way - standing, lowering my upper body and bringing my head to my knees. Or doing the same in the floor. Or lying down and pulling my knee to my chest. I always feel it in that hip flexor (i think) area.

Another interesting thing is, when I lie down on the floor and let my feet fall to the sides, the left foot (injured leg) doesn't go all the way down like the other one does.

Also, if I'm standing straight, when I pull my knee up and then release again down, it makes a loud click that resonates through my body. More lick a CLUCK.

I'm sorry it's a bit long description, just wanted to pass all the info.

What does it sound like and what do you suggest? More rest, start doing exercises, stretching, etc?

Thank you in advance,

Andre