I took my dog over to a friends house a couple days ago while we were over there her female dog was in heat since then my dog has been very anxious acting and I noticed that his penis is swollen or still erect like his pipes were clogged what can I do

How long has it been out?

When a male dog gets an erection it can take a while for it to go "back in" for lack of a better phrase.

Now, if it's been "out" for hours, then it's a concern.

If he's just getting erections more frequently, then I really wouldn't be that worried. I would get him neutered though, that will help a lot.

How old is the dog?

From the description given, it sounds as if he is just excited and that there is a bulge that has formed mid shaft and the penis itself, is not hanging out. If the penis were to be hanging out, you would notice something pink sticking out.

This bulge is perfectly normal for a dog that is excited. Even after being neutered, when the dog gets overly excited, this will happen.

He is still excited because that female dog is still on his mind. Animals have a one tract mind.. and that is to breed. To spare yourself of his excessive whining and over reaction to a female in heat, get him neutered. You would also be saving him from the possibility of getting testicular and prostate cancer.