My pulmonary artery was sightly enlarged on chest X-ray & CT (having chest pain, dizziness).Echo showed I do not have pulm htn. Should I be concerned of arteryll? 'm being treated for ctd, likely lupus

No, but follow. It is not a big deal if you do not have plum a. Htn (pah). You may just have a generously sized pulm. A. However, since you are on treatment for a rheumatologic problem, you should follow up every year with a cardiologist for a repeat echo to evaluate for pah and any other problems related to your ctd. Echo is much better than ct as there's no radiation and it's an exam of the heart at work....
No. Sounds like you have anatomical variation. Your physician is the best guide. If you are not satisfied look for 2nd opinion.