No pain, no gain !!

For me it's, no gain, cause i don't want the pain!!!

"Normal?"  Uhhhh.  What's that?  How many "normal" people do you think are on this board?  Just sayin'.  And you say you're straight?  Are you sure?  Does your definition of straight include having someone else shove something up your ass?  
OK, I don't want to pull your chain too hard, but think about some of the assumptions your question included.  Personally, I have no more interest in questioning your "straightness" than I would your "gayness."  No one here has any right to question anybody's sexual expression.  So, if you wanna do it, get it on and don't worry about what anybody thinks (even yourself).

a nice slow and easy prostate massage.. Then decide if you want to pursue things abit more indepth...

I assume you have tried prostate massage and liked it. If this is to be your first time start small.

I am talking about a finger here. A few weeks ago I went in for my physical, and my doctor realized that I have not had a prostate exam yet. He proceeded to tel me it is not going to be painful, and he would be very gentle.

He used so much lube, it was dripping all over, he tried and tried to find my prostate, but could not, so we changed position, and finally found it. He apologized for the time it took, but claimed my prostate was so small, it was hard to feel. It was very uncomfortable, painful.

Anyways, I could not walk or sit strait for days, and that was just a finger. So, I can only imagine the pain associated with a strap-on.

For myself, my arse is off limits period. I have heard that some men like it, and enjoy it, and they are supposedly strait!!!

So, good luck, and please report back on how it went if you go through it.

If it hurts, you're not doing it right.

*not enough lube
*not enough warm up
*not enough patience

and if the Top is wielding a larger member, perhaps not enough training in general for the bottom.

There are also different types of strap on experiences people might prefer over others.  Some want to be dominated and want it a little rough.  My preference is for a more sensual and connected approach...teasing to the point of making someone beg for it.  

Communication is key.  No 2 people like the same things the same way for the same reasons.  Pick a partner that is a good listener and communicator (including checking in with you all throughout to ask for your feedback), and make sure you let someone know when you want them to slow down, back off, or go to town! Understand that when you are new, your tolerance will be less then if you play that way more often.  Also-not everyone enjoys the same type of lube, so be sure to experiment if you don't like one (and don't get numbing lubes or you will not feel anything to know if someone is hurting you.)

xoM