It's early days yet. I had something similar and it was about three weeks before I was allowed home from hospital. Improvement was rapid after that. It takes quite a long time for the swelling to go down - months probably. But it does get better!!! When your tongue goes down, speech and swallowing will be a different story altogether:)
I had lichen planus too. Went to many doctors and specialists over about 6 years before someone decided to biopsy it. I also have the dysplasia but my surgeon is not too worried about it.
I know what you are going through and wish you all the very best. Let us know how you progress.

1996, ovarian cancer surgery + cisplatin and taxol.
September, 2007, SCC of left lateral tongue. Excision.
October, 2009 recurrence in scar tissue, T1NOMO. Free flap surgery from left wrist - neck dissection. 63 year old New Zealander. No chemo, no RT.
February, 2014. New primary in left buccal mucosa. Marginal mandibulectomy, neck dissection, right arm free forearm flap. T1N0M0 but third occurrence and some areas of concern: RT started 8 April and finished 19 May.