Note 6 - Equity Transactions (Details Textual) - USD ($)		1 Months Ended				3 Months Ended		12 Months Ended
	Nov. 19, 2021	Jan. 31, 2022	Mar. 31, 2021	Jan. 31, 2021	Jan. 31, 2020	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Jun. 24, 2021	Dec. 08, 2020
Common Stock, Shares Authorized (in shares)						20,000,000		20,000,000	20,000,000	10,000,000
Proceeds from Warrant Exercises						$ 0	$ 7,584,092
November 2021 Public Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)	1,950,000
Shares Issued, Price Per Share (in dollars per share)	$ 6.00
Proceeds from Issuance or Sale of Equity, Total	$ 11,700,000
Underwriting Discounts and Commissions, Percent	7.00%
Payments of Stock Issuance Costs	$ 927,000
Warrants Issued in Connection with December 2020 Public Offering [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)								1,599,204
Proceeds from Warrant Exercises								$ 7,991,101
Warrants Exercised in Net Share Settlement [Member]
Class of Warrant or Right, Exercised During Period (in shares)			9,436
Stock Issued During Period, Shares, Warrants Exercised (in shares)			2,913
Warrants To Purchase Common Stock [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						2,048,186
Warrants To Purchase Common Stock [Member] | Minimum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 5.00
Warrants To Purchase Common Stock [Member] | Maximum [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 50.00
Warrants to Purchase Units Sold in May 2016 Private Placement [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						4,800
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 25.00
Warrants and Rights Outstanding, Term (Year)						7 years
Warrants to Purchase Units Sold in February 2017 Private Placement [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						1,641
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 35.00
Warrants to Purchase Units Sold in October 2017 Private Placement [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						2,400
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)						$ 25.00
Warrants to Purchase Units Sold in May 2016, February 2017 and October 2017 Private Placement [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)						17,681
Warrants and Rights Outstanding						$ 474,852
Share-Based Payment Arrangement, Nonemployee [Member]
Stock Issued During Period, Shares, Issued for Services (in shares)				10,000
Stock Issued During Period, Value, Issued for Services				$ 50,300		$ 41,004	$ 50,300
Director [Member]
Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture (in shares)				53,938		11,327
Shares Issued, Value, Share-Based Payment Arrangement, before Forfeiture		$ 41,004			$ 271,308