I have PSTD and trip without issue.
However - every individual is different; everybody's source of - and coping strategies with - traumatic events are different.
Have you received counselling for your post traumatic stress, or are you still? This can make a big difference IME.
As was previously mentioned, set and setting are extremely important. This can't be stressed enough.
One classic symptom of PTSD seems to be a constant state of alertness, anxiety and anticipation. You may want to do some breathing, stretching and/or meditation exercises prior to tripping, in order to calm any pre-existing anxiety.
I find with many pychs, the come-up can be the most difficult, uncomfortable part of the trip. Be aware of this, and the fact that it will pass when you are fully immersed in the psychedelic experience.
Without knowing the particulars of the trauma you experienced, it is hard to know what else to advise - if you are still having flashbacks or struggling to cope with memories of the event/s that led you to suffer this condition, i recommend caution.
An empathetic sitter or trip buddy (who knows and understands your history) could be really helpful - and having some benzos or some sort of non-drug distraction to calm you and redirect your thoughts (should things get difficult) is worth considering. Fruit, art supplies, music - anything that engages your heightened senses is good to have around (in any trip).
I was an experienced tripper before the events that led to my PTSD symptoms emerging - but I've pushed further and deeper into inner space since that time - moreso than anyone i know peraonally - and at no point has the post traumatic stress been an issue in a trip.
We're all different though - my experiences and yours may be completely different ends of the spectrum.
If anything, good, enjoyable trips have been extremely therapeutic for me, and even more difficult ones have been great learning experiences.
But in both cases, I'd say my mental health has (in the short term, post trip, at least) benefited from the perspective gained from psychedelic experiences.
I don't find it unusual to go from uncontrollable laughter, to deep sobbing tears in a trip.
I find neither of these things bad or troubling - crying in a trip can be really cathartic, so long as you are able to let go of the sadness and move on.
Sometimes the emotional extremes can be a release from having been being bottled up so you can cope day-to-day; tripping is a chance to let go of 'the everyday' - and go with whatever is happening inside.
Go with it - but allow yourself to move away from heavy emotional extremes too.
You may not have any negative emotional reaction at all - it could be a blissful escape.
But if you are feeling vulnerable arond time you plan to take acid (beyond the completely normal jitters in the lead-to a new experience) it's worth assessing whether or not to postpone it to a more emotionally balanced time for you.
I agree with the post above stating that "if you were ok with mushrooms, I think you'd be fine with LSD".
I think - from the little you've told us - that I would tentatively (and with the aforementioned caveats) imagine that you should be fine to trip, if you think it's something you want to do. I find LSD brings me a fresh perspective that few other drugs are capable of producng.
You hopefully know yourself well enough to judge - LSD can be a great teacher, a great mental and emotional liberator; when the set, setting and individual mindset is all right.
If you chose to do it, enjoy yourself!
It could be a wonderful way to liberate yourself from the difficult shackles PTSD imposes upon those of us that suffer from it.
Be safe, and approach the trip with as calm a mindset as you can create.