Castration - question?

Hi all, long time since I've been here.
Deebo is 7,5yrs old, he's very healthy, very friendly, but can be dominant with some dog males, when in a group of dogs he will get on with the group.
We've decided to castrate him, well my OH wanted it more than me. I still think we've made a mistake. But its done. What we wanted to achive was calmer, no marking, no humping dog, that doesn't leave all his lovely marks on our furnitures. Now to my question.
I've noticed that Deebo is more anxious around dogs, always ready. The other day I've met a lady with German Shepherd female, they know eachother, both dogs were on the lead, laying on the grass, while we were talking. At some point the lady and I came closer to eachothers, shoulder to shoulder, the female jumped to Deebo with a growl and Deebo went for her snapping, showing teeth. One word from me and they were calm again. That was new to me, cause A) he was always fine with dogs he met before; B) he was always fine with females.
It's been 3 weeks since the castration. Why is he acting this way? Is it because the hormones need to calm down? Or this is how he's going to be from now?
I'm really upset, cause I want all the best for him, he's my baby and I feel like I let him down.

Welcome back I'm no expert on these things but if he is more anxious now & showing what sounds like fear aggression I don't think it's because of the op. If he was ok with other dogs before, the op shouldn't have changed that! Has something happened since his op that has upset him? Any encounters with Dogs or anything that may have scared him?

Are you sure it wasn't jealousy? You got too close to the other owner!

Hi again. Thank you for replying. Mayba I'm trying to look too deep into it. The whole process was stressful for him, he really doesn't like going to the vets. Maybe that's what it is. Apart from that he didn't have any stressful situations.

Introduce debo to older calmer dogs again be strict but fair wih him

It can take (I think) about 6 weeks for testosterone to leave the system after castrating. 

However, reading your post again, it sounds like the GSD went for Deebo first - he was defending himself.

Thank you everyone, it's just I really hope that we've done the right thing for him.

jola139 wrote:Thank you everyone, it's just I really hope that we've done the right thing for him.

I doubt that the castration was the cause of the set-to. Any dog will defend itself, and stafford's can be quite spectacular when they do!

He is probably starting to feel a few changes and it may unsettle him a little but in this case i think the other dog just made too sudden a movement and he reacted because he didnt expect it/welcome it. Could happen to any dog, any time any where. Don't read too much into it.