Thanks for your question and concern. You have taken a bold decision in helping your boyfriend and solve the problem you are facing. To reassure you, the problem your boyfriend is facing is not at all your problem. It is a usual thing to have certain anxieties to be a good lover that cause men to have the problems like this.
Majority of the men face problems with that of the erection. The main causes of the erection problems are due to the consumption of alcohol, not feeling well (tiredness), or simply having no feeling to have sex. The recent studies indicate that one among every ten men is having the problems with the getting of an erection or with the keeping of the erection. So it is a common problem. The causes for these are mainly psychological. Anxiety, fear of failures, stress etc. are the factors coming under the psychological causes. But there are certain other factors that may not at all psychological. Sometimes the real problem will be with that of the physical causes. If the problem is with the physical then it will be good to have it treated soon.
It will be good to have it talked with your boyfriend about whether he is having any psychological problems. Communication is the important thing to be taken care of. Most problems arise due to the lack of communication. Just like men most women also feel insecure.so sharing your concerns with each other is really important in keeping a relationship. If you are having a good relation then most problems will be solved at their initial stages.
It would be good to have your problem talked with someone else and clear the problem. There are several options to clear your doubts. The association named sexual dysfunction association will be able to understand your issues properly and have it cleared soon as they have several specialists with them. You could also approach a local doctor (GP), if your problem is with something physical, then with some surgeries and all it will be normal in a few days. Good luck.