Hi, my husband works out of town and the last time I saw him was two months ago and so naturally when he came we had sex on the brain,the first night he could not get hard at all,he was very upset but the subsequent nights we had sex and had no problems at all.The last night he couldn't get it up again we tried everything to stimulte him but nothing,what could this be, please help

Many men have trouble getting hard or staying hard form time to time. Strees, even over excitement, sometimes too much masturbation.

Also many medications and illness can cause it. ( besides getting old)

If it is only once in a while best you can do, is not make a big deal out of it, ( no pun intended) and just enjoy sex play and go on with life, If you make a big deal out of it, it makes him feel worst and the more trouble he has, the more it will effect and cause more issues.