When standing i have alot of pelvic and rectal pressure even in my inner thighs? also left lower back pain?

Are you pregnant now? and if you are how far along? When i was 24weeks pregnant my daughter settled on my sciatic nerve and caused a lot of pain like you are decribing i had a hard time walking. I would get checked out by your doctor!

You may have a kidney infection.
Oh my! I had the same thing. My dr. called it "round ligament pain" but it felt like my insides were just going to drop out!! Horrible feeling!

The cure? HAVE THAT BABY! :)
YES YES YES... it is called 'round ligament pain' and it is really annoying! I have had it since my 2nd trimester (I am almost 39 weeks along now). The best thing I've found to help relieve it is to utilize a BIRTHING BALL (aka exercise ball). You just straddle it & kinda rock back & forth or side-to-side.... you can keep your legs close to the ball or straighten them out and stretch them. It stretches the ligaments down there & provides massage in that region. You'll love it! It also helps late in pregnancy for the baby to 'engage' into the pelvis & offers back pain relief. Hope this helps!
39 weeks and feeling the pain!
One trick I used that felt awsome was to roll a body pillow up in a U shape, and het a couple more normal pillows, place your belly in the center of the U and position the sides of the pillows under your hips. Use the other pillows to support you upper body, and have a nice sleep. You could also try and go to a pool for a swim, the water is great because it takes all the pressure off your body and supports the weight of your belly. Don't worry, not too much longer to go, but the last 2 months suck!
I had the same problem, it was the baby laying on my sciatic nerve. But the pelvic and rectal pressure will continue until you give birth. Just check with your doc just to be certain.