...Everything was very painless and as soon as I came out of a anesthetic, I touched my knob to see how sensitive it was and I couldn't even feel it. However, I now know that was just due to the numbing crap as I can definitely feel it now! ...Peeing itself doesn't hurt but the penis head rubbing against my underwear is very painful! I don't know whether to wear tight undies or loose undies, as the doctor told me to put some pads in my undies to catch any bleeding, but if I'm wearing boxers then the pad will just fall out! ...
		
		
	 
	
		
	
	
		
		
			^If you buy a pair of those plain white briefs, you could probably put a Kotex in there that won't fall out.
I say that without a touch of sarcasm.
		
		
	 
Numbness is an expected result of the surgery.  There is a local anesthetic administered during the surgery- similar to the local that you get at the dentist's office.  The local lasts for several hours after the surgery, as does the pain medicine they give you after the surgery.
Surgeons usually forget to mention that 
any surgical incision will cut through nerve endings.  It can take 6-12 months for sensation to completely return to the area around the incision, which in your case is the circular line around the foreskin.  So, this makes for a very weird mix of sensitive and numb for a while.
It's good that you're able to pee.  We always worry about that.
You surgeon should have given you instructions on:
- When you can shower
- When you can bathe
- How long you have to leave on the bandage and whether the surgeon wants to be the one to change the bandage the first time
- What type of stitches you have and when he will remove them.
- When you can take your new dick out for a test drive.
If you weren't given these instructions, call his office and ask the nurse.
If the surgeon didn't make it clear:  lay around and don't do shit for a couple of days.  After any surgery, if you're standing up, moving around and trying to do too much activity, it will make your swelling and bruising worse.  This is a good time to lay in bed, read and watch TV for a couple of days.
You can expect some bleeding at the surgical site- this will continue for 2-4 days normally.  Sometimes the bleeding may be worse on day 2 or 3 and you may find that you bleed after you get an erection.  
There's several things that you can do if you're having some bleeding or minor drainage at the surgical site.  But you may have to do some experimentation to find what is most comfortable for you.  
Every guy is different, so dependent on whether you're a shower or grower, the bandage will be different.  In general, it's like a weird sausage wrapper that is intended to apply compression.  It usually has a hole that you can pee through- although it also tends to make you spray a bit when you pee.
Once the compression bandage is removed, then it gets more complicated.
- Some guys put on an old pair of snug (not tight) briefs and then apply a little petroleum jelly and a bandage (either a small square or the wrap-around style).  Use a pair that you are going to throw away since they may get some blood staining.  If you're not having a lot of pain, this might work best for you.  
- Some guys find that anything rubbing against their penis is painful.  They chose to boxers, sweatpants or just go without pants if there's no one around that hasn't already seen them naked.  If you go the boxer route, you can use a maxi pad or maternity pad in your underwear (the old style pads come with a belt, the newer ones have an adhesive that sticks to the underwear).  If you end up going the naked route but you're still having some bleeding, apply a bandage to the area or fashion a soft dishtowel into a kind of diaper.  Not pretty, but functional.
Once the outer bandage is removed, there is often a small round bandage that is over the incision line and covers the stitches.  It usually gets soaked in blood and sticks to the scab which makes it difficult to remove.  The surgeon should give you instructions on when and how you can remove it.
The erections will be worse after the compression bandage is removed.  They will be more likely at night (when you are usually asleep and normally don't know you're hard).  And the erections will hurt until the stitches are removed.