Did the Romano Britons have a name for what is now England?

Brittania.

The ancient name for Britain was Albion; etymologically derived from the Greek Ἀλβίων, and Latinised as Albiōn.

In the first century, Albion was replaced by Brittania, initially in reference to the whole of Great Britain, while the Scottish region outside of the Roman regions was known historically as Alba.

It initially was used to describe Great Britain in its entirety, but Tacitus and Cassius dio later applied it exclusively to the provinces of Roman Britain and the Southern parts of the areas. The unconquered Northern stretch and portion mostly comprised of Scotland became known as Caledonia, the etymology of which is murky but might have been derived from Welsh or the proto Celtic tribes in the regions outside of the Antonine Wall.

Alba was also used inside the region by the indigenous peoples to describe Scotland, and like Albion, it was later frequently used to describe Scotland in the romantic sense.

Records predating Roman occupation of Britain used the Albion title, and while Ptolemy also used Albion in his 2nd century writings, 1st century classical writers from Britain used Brittania broadly.

Albion remained in use romantically throughout the 2nd-10th centuries by some writers and Kings, and especially during the English Renaissance, but this was more poetic licence than accurate region naming.

All of these names were used variously by different persons, to describe ever evolving territories and there is much overlapping amongst them. During the Anglo-Saxon and Heptarchy periods, Englalande replaced Brittania as the name of the island as a whole, while individual kingdoms bore their own place names. Englalande was eventually shortened to the imminently more recognised England. Elizabeth I revived Brittania in the romantic sense, and Britain evolved from that.

TL; DR: Welcome to Britannia.