Firstly, prostate cancer, unless it’s advanced, which it assuredly isn’t with a PSA of 7, doesn’t cause aches and pains. That’s just an overactive imagination thinking the worst. You may have PCa (as we call it in these parts), but localised PCa is eminently treatable. Don’t worry - a PCa diagnosis is not a death sentence!
As you say, next will be a visit to a urologist. He or she will do another DRE (they’ll be much better at it than your GP!) and then probably an MRI scan and a biopsy. Don’t stress about the biopsy - believe me, the anticipation is far worse than the event! It’s not pleasant, but it’s roughly the same order of “not pleasant” as, say, having a filling at the dentist. About two weeks after the biopsy you’ll know the result.
I said “don’t worry” earlier, but that’s me looking back on it from the other side of the experience. It is a worrying time, and you’ll be waiting a long time (at LEAST a month, more likely two months) until you’ll know what’s going on one way or the other. All I can really suggest is keep yourself busy and try not to dwell on it. Even if it is PCa, it’s curable. You don’t die from localised prostate cancer, although you may well die with it.
This site has loads of useful information leaflets. Download them and read them. Phone the freephone number and talk to the nurses if you have any medical questions - they’re wonderful people.
You’ve come to the right place to get support. Welcome to the club! We’ve all (well, all of us of the male persuasion at least) been through it and know exactly how stressful a time this is.
All the best,