First Dogging Experience

Husband and I have been together for ten years and married for six now. We’ve always had an active sex life and about five years ago my husband confessed he had a fantasy of sharing me with another guy. It was a massive turn on for me, thinking about being center of attention and having two cocks to play with so we explored further and found a guy online who came and joined us. It was exciting and enjoyable for both of us and since then we’ve had another six threesomes, three planned and three quite spontaneous. A couple of months ago we were watching some amateur porn and both got turned on watching a girl at a car park play with a group of guys. Hubby said we should try that and so we found a place, a little away from where we leave so we wouldn’t be recognized, and a couple of weeks ago went for the first time. My husband helped me get ready and picked out a black g-string and bra set which I wore with heels and just a coat over. We agreed I would just wank and maybe suck a guy or possibly two but not have sex. I had a couple of drinks as I was nervous but we were both excited.
When we arrived we saw a couple of cars parked and so we did the same. I opened my coat as husband and I kissed and his hands teased me. As his fingers played with my pussy I saw we had an audience with three different guys watching. My husband asked if I was ok and sure to which I nodded and he let the window down. Hi guys he said as his fingers continued to stroke me. I giggled and unhooked my bra. As I slipped out of it a guy took that as an invitation putting his arm in the car and starting to play with my breasts. I closed my eyes and lay back enjoying the attention, pulling one knee up to expose my pussy completely as husband spread my lips for everyone to see. The guys outside swapped positions and took turns touching me and as husband sat back replace his fingers stroking my pussy. After a bit husband whispered in my ear shall we open the door? I nodded, to turned onto speak, and he got out of his door. I watched him walk round to my door and he told the guys to step back and I would get out so they could all touch me together. He told them no sex tonight but if you turn her on she might wank you off.
Getting out I shrugged off my coat and stood there in the evening warmth, and as the three of them crowded round I took a cock in each hand and wanked them. After a couple of minutes the first said he was close to cumming and as I squatted down I naughtily told him to cum over my breasts. He quickly shot his load at which point the second guy also said he was ready and exploded a huge amount over my chest. As I was dripping he quickly got back in his car and drove off but by then I had called the third guy forward and being so turned on was greedily sucking his cock. As I did my husband had knelt beside me and was busy fingering me hard whilst rubbing my clit with his other hand. I took the other guys cock out of my mouth and as I shuddered to my orgasm he added a third load to my chest. He and the first guy then watched as husband lifted me up, spun me around, bent me over the car and plunged his cock into my soaking pussy. He fucked me hard for a couple of minutes then I felt him shoot his cum deep inside me. We said our goodbyes with the guys asking when we would be back and as we drove home I rubbed their cum into my nipples and sucked my fingers enjoying the taste.
I was on a high and really enjoyed my first experience. Husband however is a different story and has said he doesn’t want to repeat this. He said he has never seen me look so slutty and thinks if we go again I will end up letting anyone who wants fuck me. I can’t argue because that is exactly what I fantasize about but really do want to explore this side of my sexual side. Any ideas how I can convince him ?